None of the YouTube videos seem to be linked in the post, but they are available here: https://www.youtube.com/@MichaelGrahamRichard/videos

Where does this hero worship of JVN on this site come from?

It comes from the people who worked with him. Even great minds like Teller, who you mentioned, held him in awe:

Edward Teller observed "von Neumann would carry on a conversation with my 3-year-old son, and the two of them would talk as equals, and I sometimes wondered if he used the same principle when he talked to the rest of us." 

Nobel Laureate Hans Bethe said "I have sometimes wondered whether a brain like von Neumann's does not indicate a species superior to that of man".

Claude Shannon called him "the smartest person I've ever met", a common opinion.

https://en.wikipedia.org/wiki/John_von_Neumann

To my knowledge, no one else in history has had such a large impact over so many fields (mathematics, physics, computer science, engineering, statistics, game theory, economics). If he had been an economist and nothing more he would still be famous.

Peter Lax commented that von Neumann would have won a Nobel Prize in Economics had he lived longer

Paul Samuelson wrote, "We economists are grateful for von Neumann's genius. It is not for us to calculate whether he was a Gauss, or a Poincaré, or a Hilbert. He was the incomparable Johnny von Neumann. He darted briefly into our domain and it has never been the same since."

https://en.wikipedia.org/wiki/John_von_Neumann

Looks like you are right. I was confused because two paragraphs after the fall Willy is described as injured with no explanation how. And the phrase "apparently uninjured" seemed to foreshadow that whoever fell was injured after all.

[Wikipedia](https://en.wikipedia.org/wiki/Toni_Kurz) [explains](https://en.wikipedia.org/wiki/Willy_Angerer) what happened:

"During the ascent, [Willy] Angerer was injured by falling rocks loosened by the warmth of the rising sun as they crossed the first ice field."

"A rock fall injured [Willy] Angerer in the head on 20 July 1936, forcing them to descend."

One last typo:

"Hinterstoisser fell 37 meters down the mountain face" -> "Willy fell"

I see! Thank you for the detailed explanations. 

Regarding point 1: The posterior percentages are shown to 5 decimal places, so I wrongly assumed that 1.0 db meant exactly 1. 

What do you think of showing the sum of the decibels of all pieces of evidence? That would have prevented my confusion. 

You could also include 2 digits after the decimal for quantities smaller than 1.1. (Although this has the cost of introducing clutter.)

Things I like:

1. The dark color theme looks good
2. It's nice to be able to set the hypotheses as a non-percentage, such as 10:1, and then click "%" to convert to a percentage.
3. Being able to see the decibels for each piece of evidence is nice. So is being able to link or export a calculation. 

Possible improvements:

1. Adding 10 decibels of evidence results in a different outcome depending on whether the decibels are added one-at-a-time or all-at-once. Compare [case 1](https://bayescalc.io/#KCdoLWVzKic3QSd-N0InMnAzMTQsMS4wMnBvc3RlMzU0LDU0MmU2KidFNiAxJzJsaWtlbGlob29kcypbNDEsMC4xXV0pKiFbLXlwb3RoZXMyXX4zcmlvcl9vZGRzKjQwLjA2dmlkZW5jZTdILWlzIAE3NjQzMi0qXw==) and [case 2](https://bayescalc.io/#KCdoRmVzRCdLQSd-S0InSXBKMTAuMCwxLjBJcG9zdGVKNTEuNzc3OTg5NTA1NDA5MTMsNDguMjIyMDEwNDk0NTkwODc2SWVHRCdMMS0yLTMtNC01LTYtNy04LTktMTAnSWxpa2VsaWhvb2RzRE1NTU1DXSlDLC0nfkxDKlswLjA4LDAuMV1EIVtGeXBvdGhlc0d2aWRlbmNlSV1-SnJpb3Jfb2Rkc0RLSEZpcyBMRUcgTSoqAU1MS0pJR0ZEQy0qXw==)
2. When the "help" is open, the "add new hypothesis" button and decibels are hidden. 
3. A button to toggle between showing decibels and bits of evidence would be nice. I more naturally think in bits. 
4. Enable equations in the evidence percentage fields. It's nicer to type 1/3 rather than 33.3333333333.
5. Allow deleting any piece of evidence, not just the last piece.