Adding some anecdotes... there is a 1 mile long dead straight 10% grade that is the "end" of one of my weekly summer evening rides, and the fastest I have ever been able to go down it is 55mph. Even aero wheels didn't really help. However, there is a much heavier guy (50-60 pounds on me) that would do the ride with uus sometimes and he could get up to the mid 60s. A few times I tried to draft him down and couldn't even hold his wheel. Neither of us were doing any super-aero positioning... I'm sure if I dropped down into the frame and put my hands at the center of the bar I could go faster but my balls aren't big enough, especially on that road...
Ah... "climber's balls". It's a syndrome. But there are treatments...
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Cat 2 Track, Cat 3 Road.
"If you’re new enough [to racing] that you would ask such question, then i would hazard a guess that if you just made up a workout that sounded hard to do, and did it, you’d probably get faster." --
the tiniest sprinter