Replying to Most useful thing learned on ski forum?

Yes there's a plethora of knowledge on the internet for skiing these days.... but what is the single most useful thing you have learned on a ski forum (this can be NS or elsewhere)?

Before I joined NS, I had an account on onthesnow forums before they shut down. Someone had a thread that included a video on how to self-arrest. I'd never heard of it before that day, and turns out I ended up having to use it a mere 1 month later. I tried all the basic stuff and ended up having to stop my slide by jabbing my pole into the ground. Probably slid 100yds. Had I not seen that thread, I woulda gotten real fucked up. That thread saved my ass and I consider it one if the most useful things I've ever learned on a ski forum.

While I've learned so much on NS, this has to be the most important thing I've learned. How bout you?