kubami

In the context of this post it's not about preserving or sharing the thoughts. Writing, in this case, is a "thinking tool". Forcing yourself to materialise the thoughts as actual, written, text helps form clear ideas.

Are there any good forums where people do have good market knowledge and share it?

By no means it is an outdated phrase. Ask any startup sales person!

But isn't this one of the points of all this. Figuring out which thnigs work and which don't? Which can be thrown out and which can be "condensed"?

I think it makes sense. He's doing the most extreme things to find things that work. And then be able to say, "This subset of intervention worked very well, let's try to reproduce it in a larger population."

Maybe if he was not doing anything, his score would be 1.1?

Also, I don't think the point is doing fancy things. The people that beat him might just be doing "common sense" healthy things. Something which most people don't do. See SAD (Standard American Diet).

Exactly this! I haven't been interviewed for a long time now, but since the beginning of my career, when I have interviewed people I ask deeper questions. Even with tech tests, I use them as a jumping board for diving deeper into language design, tradeoffs and experiences. Even a trivial, reverse-a-string kind of questions can take you deep into candidate's knowledge.