Originally Posted by
steelbikeguy
I'm unfamiliar with any need to brace against the saddle while shifting. I'd be more inclined to say that it was a common behavior in those learning how to reach to the down tube levers than in all but the best.
Or perhaps it is related to core body strength?
When I say "brace", I don't mean clamping the saddle, I mean to make some amount of contact with the saddle.