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Guess I'll watch it live via esVPN

Helmets don't have a shelf life - that's a myth. They certainly get worn out with use, abuse, or improper storage, but time isn't what does them in. https://pubmed.ncbi.nlm.nih.gov/26902784/

I finally got a used one just in time for my last mountain bike ride at Vital Ditch Day a few years ago. I wore it without all of the fancy straps and had no issues with comfort or it hitting the back of my helmet.

There was a 10 year study on neck braces that everyone should read - https://www.actionsportsems.com/case-study-neck-brace. I've been wearing one for years. As far as freedom of movement etc - invest the time in setup and also have your brace on when you're trying out helmets to check for interference.

I still occasionally use my Alpinestars neck brace when I ride Moto. But it has definitely fallen out of favor in the Moto community with very few riders using it. You can on occasion still see the OG neck protection, the donut! Lol i think Carson Mumford uses it sometimes.

Some moto guys still wear them. I do not. I tried one once and after two laps, the jury had decided: NOT FOR ME. The brace interferes with my movements too much. I wonder if that's the concern among DH guys?

Yes. They basically have to use marshalls to make sure that the World Cup DH guys are actually wearing the padding that the rules mandate, from what I understand. I've heard talk of racers taking the padding out of their pads and such to reduce the distraction. Edit: It's also possible I"m conflating something that I KNOW happens in American Football, especially for high speed positions as well as an incident I remember reading about where a country's regulating body (maybe Italy) was requiring DH riders to wear spine protection, and a lot of them were complaining because they never...