I’ve seen some people try to use the Microsoft outage as blame for a hotel pool in Germany that pumped too much chlorine into its water. Just because that hotel configured poison warnings for email does not fault the email. Everyone and their dog knows email is never guaranteed delivery. It is not a reliable alarm.

The pool belongs to Hotel Ling Bao at Phantasialand in Brühl, and fifteen guests were hurt there on Friday. Let’s dive in.

The main duty to protect those guests belonged to the hotel. Section 37 of the Infection Protection Act requires pool water that poses no risk to human health, and the federal environment agency’s guidance applies that requirement at all times and in every part of the pool. One state health office’s guidance on DIN 19643 also has the pool operator measure free chlorine by hand three times a day and compare the result with the instruments. Thats the real story here.

A hotel can hand the task of watching the water to a machine. The hotel duty to stop the dose, close the pool and warn the guests does not change hands just because an email service was setup. But people are reporting that the hotel handed the task to a monitoring system using email. It sends a message when chlorine is outside the normal range. Their message depended on Outlook.

But also consider the danger of a false negative configuration. No email means no poison by hotel operator design, despite no email being possible for a million other reasons. A positive system would have sent an email to confirm safe levels, such that a delivery failure would itself be an alarm.

The first to know that this backwards and faulty hotel arrangement had stopped working was the public. Microsoft reported the Outlook outage shortly before 1 p.m. Eastern on Thursday, which is early evening in Brühl. So the hotel in theory knew they had no alarms running. German television covered it from 7 a.m. on Friday. From Thursday evening the hotel safety alarm was disabled, accordong to public notice by the vendor.

The second step of this design failure was a missing fail safe. On Friday the automatic dosing system failed unsafe, meaning it pumped too much chlorine into the pool. The monitoring system even tried to issue an alarm by email. WDR reports that the alarm had gone out by mail long before anyone human noticed and measured the poison.

The third step was the guests entered the poisonous pool and then thirteen of them reported irritated airways. Their complaints brought about 30 firefighters and ambulances from four neighbouring towns, and the count rose to fifteen. Four went to hospital and one stayed for observation with moderate injuries.

The staff running the pool somehow were the last to know, when they were supposed to be the first. Every one of the fifteen guests was hurt after the email outage became public on Thursday evening. Their complaints came after the machine had sent its email alarms. WDR’s report gives no time for that alarm and says nothing about the hand measurements on Friday. Those two facts will show how long the pool stayed open with too much chlorine in it and whether the hand tests were done.

Phantasialand told WDR, when asked, that the Microsoft outage was the cause. Nonsense. Microsoft had no duty to the guests in that pool, not least of all because it was just an email service provider. The hotel retains the duty and should be held accountable for a warning that depended on email. And held accountable for how they responded to email outages.

A safer design is easily available. One German controller manual describes an upper alarm value that halts chlorine dosing by itself, because a failed measuring cell can cause dangerous overdosing. That fail-safe cut-off works beside the pump. It doesn’t need a faulty alarm to a human. The danger of a faulty alarm design was also known in Germany. A DGUV study of 187 chlorine gas releases in German baths counted 91 with injuries, and one of its examples is a dosing fault message that was left off the panel at the permanently staffed post.

It is a known harmful design with a history of harms, being allowed to harm again. German law lets the hotel choose faulty messages for poison prevention, a predictable disaster. When you really think about that, Germany once had a word for gassing people in baths. Of all countries they should be the place to have the prevention part figured out. Nobody seems able to remember, however. That surely has something to do with the slipping obligation of never forget? Perhaps some alarm mail from 1932 has not yet been delivered?

Section 37 is silent on how an alarm travels, meaning here was not at all. The ordinance that would have set binding monitoring rules for pool water failed in the Bundesrat in 2003. So the duty to self-regulate poison in large baths has stayed with the operator ever since, and so has the design of alarms that would prevent people getting sick or dying.

I’ve been asked as a historian what I think of historian Heather Cox Richardson. In particular, since I am a historian who has posted nearly every day to a blog for about 20 years, I was asked about her blog popularity. I was asked what do I think of her posting every day to her blog for seven years, rising to millions of followers.

Well, not much, honestly. I had never heard of her before I was asked. And when I was asked, I looked and found that she was publishing things that seemed factually wrong. I also don’t honestly know how many followers I have. I don’t track and advertise, or take paid subscriptions, so we’re fundamentally different on the platform as well as the points.

Take December 28, for example. Since 2019, she has republished her account of the night before the Wounded Knee Massacre. She revises it each year. It’s kind of like how I was doing the exact same thing for Thanksgiving Day starting back in 2005.

I’ve written about Thanksgiving history here many times (2005, 2006, 2008, 2010) and this year it feels like time to write again.

When I did a diff across her annual posts, I found the name “Big Foot” was dropped in 2023. And “a dozen years ago, I wrote a book” became “fifteen years ago” in 2024. I get that. But then I found a sentence rising up again and again, through all seven editions without edit:

In came three mountain guns.

Huh? Why does she say three? I’m not saying this to be pedantic. It’s rather important in the detail of military strategy from that time to know the exact type, number and position of guns. Such details are literally how people learn to win the next battle, or even a war.

The Army counted four. So why three?

Major Samuel Whitside testified to the court of inquiry in January 1891 that his column reached Wounded Knee Creek with “two Hotchkiss guns, under Lieut. Hawthorne,” and that Colonel Forsyth arrived at about 8:45 that night with “one section of Hotchkiss guns, under Captain Capron.”

Two guns were on the hill at dusk. Two more came in after dark. That makes… NOT three.

With all due respect, Richardson works full-time on history and she wrote the book on Wounded Knee. A specialist in the Army’s files calls her book “phenomenally researched.” And yet her newsletter, Letters from an American, which reports more than three million subscribers, doesn’t seem to hold the line.

I suppose we could call this one mistake a small thing. I suppose we could even say repeating it annually, increasing the chances of it becoming repeated by others, is a small thing. But my own training begs me to ask how big of a pattern can I find from the small thing. I think the gun is a bigger symptom than most people would notice, and it’s certainly something that LLM vendors get raked over the coals about.

So, being an old disinformation analyst by formal training, what could I do but pull all of her 2,300 letters, from September 2019 through November 14, 2026? I’m not interested in her current politics or even her arguments. Although, let me also point out that facts affect the arguments, as I explained already in another post about her.

A historian reproducing mythology as a settled fact marks a synthesis drawn from a disinformation canon, rather than the scientifically corrected record.

This time I pulled every passage about events before 2000 and extracted the dates, counts, names and offices that disagreed with a reliable, primary source. Then I double-checked it all. Every example in this post I verified by a linked source. Primary sources have the correct answer, so it’s mostly just a simple math test about the drift in her texts, a simple plus or minus.

Interestingly, there are 524 letters about an event in history with a date. Of those, 96 have at least one factual error. Of those, there are 68 distinct errors that I found 109 times. She tends to repeat her errors when she posts re-runs. That’s just a start, because quantitative analysis seemed to be the right path into qualitative.

Slop is a word we use for automation machines. It’s a derogatory term about the high cost, high output and low integrity. Each of her letters isn’t brief, usually over a thousand words and a page of source notes. It seems to be on the end of high cost and high output, so I’m asking here if there is there evidence of integrity issues? Or perhaps more to the point, is there a lack of an editor doing the pre-publication pass that a book deal would impose upon her?

Richardson Claim	History
“In came three mountain guns” (every December 28, 2019 to 2025)	Four Hotchkiss guns: two with Whitside, two with Forsyth (Whitside testimony, 1891)
“That night, America declared war on Japan” (2019, 2021, 2023, 2024)	Roosevelt addressed Congress at 12:30 p.m. on December 8 and signed the declaration at 4 p.m. (National Archives)
Tennessee ratified the Nineteenth Amendment “by a vote of 50 to 49” (2022, 2024, 2026)	The House voted 49 to 47 after a 48 to 48 tie; the Senate voted 25 to 4 (National Park Service)
“Parliament in 1772 removed all but one of the new taxes” (2023, 2024, 2026)	Parliament rescinded four of the five Townshend duties in April 1770 (Massachusetts Historical Society)
John Lewis “in 1960 was one of the thirteen original Freedom Riders” (2019, 2020, 2021, 2025)	Lewis became a Freedom Rider in 1961 (National Park Service)
“former U.S. senator Alexander Stephens of Georgia” (2026); “Georgia Senator Alexander Stephens” (2022 twice)	Stephens sat in the U.S. House from 1843 to 1859 and never in the U.S. Senate (House Historian)

The Wounded Knee letter gives a clue how the mistakes might happen. Each December someone edits the tribal names and the author’s note, and then publishes the same text again. That is a pass for readability, making the text enjoyable. Quality isn’t being defined in terms of the accuracy, which is how the number of guns continues to be wrong.

When I looked at the Pearl Harbor letter, it said “That night” four times between 2019 and 2024. It wasn’t that night. In 2025 it corrected to “The next day, the United States declared war on Japan.” That’s great. Except for two things. The page carries no correction note and the four earlier editions are wrong. My thing about Pearl Harbor has always been the listening station being ignored. It’s a bit messy to understand and explain. But this night/day thing is a simple one.

The 2025 edit fixed the date and kept the order of events. The sentence now reads:

The next day, the United States declared war on Japan. Japan declared war on America, and on December 11, 1941, both Italy and Germany declared war on America.

Every edition has the United States declare war first and Japan second. Ugh. Why?

Japan declared first. And this one can’t be called a small error.

Japan’s cabinet released the imperial rescript declaring war at 1100 hours on December 8, Tokyo time. Tokyo was fourteen hours ahead of Washington, so the rescript came out at 9 p.m. on December 7 in Washington, about seven hours after the attack began. Roosevelt signed the American declaration at 4 p.m. on December 8, nineteen hours after Japan’s. In terms of defense theory she’s making one of the worst mistakes possible, reversing the declarations. Who declared war first matters A LOT for basically every reason we study war at all.

Richardson does mark corrections. Her letter of May 21, 2024 concludes on this line: “Edited on the morning of May 22 to correct the date to May 21. Sorry about that.” The headline date was fixed and flagged within hours. The same letter says Joseph McCarthy spoke in Wheeling “On February 12, 1950.” The Wheeling Intelligencer of February 10 reported that he spoke “last night.” Her own letter eleven days later gives February 9. Talk about a merry-go-round. At the end of it all, the incorrect February 12 date is still on the page.

One edit in fact made a true sentence false. In 2022 she wrote of the Little Bighorn: “The only army survivor of the battle from Custer’s immediate command was a horse, Comanche.” For the 150th anniversary in 2026 the sentence reads: “The only army survivor of the battle was a horse, Comanche.” Whoops. She deleted four words that erased the fact that hundreds of men under Reno and Benteen survived the battle. Again, a small detail, but it kind of is the entire point of studying Custer that he was such an incompetent bombastic disaster (foreshadowing politics today), different from others like Reno and Benteen.

Richardson Claim	History
Republicans “added five new states” by July 1890 (September 2025); “six new states,” with Wyoming and Idaho both admitted “On July 3, 1890” (February 2026)	Six states. Idaho was admitted July 3, 1890 and Wyoming July 10, 1890 (Statutes at Large)
A Joint Committee on Reconstruction “of thirteen lawmakers” (November 2025); “of fifteen members” (October 2026)	Nine House members and six senators (House Historian)
Roosevelt’s Osawatomie speech “later that year” in 1910 (November 2023); “in 1912” (March 2024)	August 31, 1910 (Theodore Roosevelt Presidential Library)

The October 2026 letter that corrected the committee to fifteen also says both chambers agreed to the Fourteenth Amendment “on June 18, 1866.” Congress passed it on June 13. I guess an 8 can look like 3 sometimes. My eyes aren’t great anymore. But a system with integrity controls is meant to compensate for exactly that kind of error. These letters float conflicting dates, where each is published with the same confidence, internally contradictory.

The November 2023 letter gives the 1912 result as “409 electoral votes to Roosvelt’s 107 and Taft’s 15.” When I checked the National Archives I found 435, 88 and 8. Very strange.

The February 2024 letter gives Lincoln “212 electoral votes to McClellan’s 12.” When I checked, McClellan won 21.

Can you see why I ran a mathematical analysis? It’s fast, it’s easy, and it’s the kind of thing my history professors hammered into me. Davi, at least get the dates right if you want to do analysis of events. It’s the kind of importance I carried straight into digital forensics investigations, where a timestamp error is death to any attempts at catching a perpetrator.

Secretariat’s “trainer” in her annual Kentucky Derby letter is Charlie Hatton, who wrote about racing for the Daily Racing Form. Nope. And the line she gives him, “The trees swayed,” is one the Racing Form says he wrote about a different horse, Raise a Native, in 1963. Her letter has the wrong job for Hatton, the wrong horse, and a conversation with Red Smith that the Racing Form’s account doesn’t have.

Jim Thorpe’s 1912 pentathlon is listed as “sprint hurdles, long jump, high jump, shot put, and middle distance run.” Yet the events were actually long jump, 200 metres, discus, 1,500 metres and javelin.

Her very moving tribute to Dolly Parton has the singer on radio and television “in Nashville by the time she was 10” and then, in the next sentence, moving to Nashville in 1964. That’s such a quick flip, did she read her own letter? I didn’t know this history, and when I checked, found that the childhood broadcasts were in Knoxville.

A horse, an Olympian and a country singer aren’t the class of error as three versus four guns. These errors maybe are a matter of fast writing that goes out unchecked, and her memory is subject to correction like any of us. But bear with me here, as a historian who has written daily on a blog for 20 years, not to mention that it has been online since 1995. If you ask me what I think about her letters, I think I’m finding a lot of errors. When I am asked to look at just one letter, I find an error. And then I look at a few more, and I start to think something is off.

The rate has held steady, by my quick calculations. Hey, maybe I’m wrong here! But between 10 and 18 letters a year have carried an error in every year since 2021. Across seven years I found only three corrections. Eleven errors were republished three or more times.

Perhaps she needs a quarterly rescan, a cleanup of the past daily posts?

Richardson is very, very popular as a writer. The Daily Show just did an “interview” that amounted to the host gushing about her love for the letters, and Richardson even fluffing the host. The only history in it at all was a single minute comparing today to the 1890s, which the host took without a single question. Shame on you Daily Show.

People are looking for the actual facts of what this country is.

You’re not going to call her out on that? Ok, then, I guess I have to be the one. This is what the host said.

I don’t think we have blue waves like this without scholars like you walking us through these moments.

Maybe the whole point is a feel-good narrative and regurgitation and re-runs of what works, to amplify and gain audience as Jon Stewart seemed to do with her. This is what she told him.

I help to show people where the ground is.

Any pilot relying on her would be shown the wrong number for where the ground is for at least 1 of every 5 flights. You want to fly on those numbers?

She is a clear and persuasive writer, and most of her history is on target. But it’s not all, and maybe reach is the reason her errors matter even more, beyond the question of whether she would accept a factual error in one of every five papers a history student turns in. If her low-quality facts get high reach, is it better than someone with high-quality facts getting low-reach? That’s a question for the ages. McDonalds or a local chef, you make the call. Three million people receive the letter as if it is the work of a historian. And the way I was trained, an historian’s authority comes from them doing the checking and re-checking, not you doing all the clicking.