Thanks for good questions, and not ZOMGZ how do you stop. which BTW, is airbrake than footbrake, and if you dont think you can footbreak at 65, you can.
Before I had hit 5o, 60 or 70 or anything like that, I had moved to Colorado. I drove around after scouting some google earth maps and found a plethora of hills, I started small ish. As I did have some DH experience, but not much. Could'nt pendy, couldnt footbreak around corners couldnt speed check etc. After riding a few months here I decided to go for this hill, I hiked it, by myself and hit 63 with a gps. I was half tucked... After that I rode the hill A LOT ive made 438 + or - a few hash marks I didnt mark. Tuck isnt very important, sure it has to be good, but its more about being rock solid, with no movement. SO id say the skills build , to ride down the hill, its not that hard. But to hit 70 plus every run, that takes a good amount of time and skill to ride fast regularly.
Im not scared. If you get scarred, theres a good chance your going to crash and never skate again.
Yeah you're right about that, one of the local riders here in Austin (Jia) hit a deer on a morning session.
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Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body, but rather to skid in sideways, cold beer in one hand - longboard in the other, body thoroughly used up, totally worn out, and screaming, Yeaa Haaa What A Ride!!!