Custom Oak Cycles 650B French Randonneur Project.

How flat is your back while cycling? How far forward is your torso?

Increased lower back flexibility can help you rotate your torso lower, bringing your hands further forward. You then need the core stability to hold yourself there without collapsing.

Good core strength and flexibility help with these things. I too have relatively short torso with respect to my leg length, but these days can get my head to my knees and my hands under my feet when doing a forward bend.

Does this necessarily matter? For a road cyclist/triathlete yes,

but for an audaxer interested in a comfortable ride at a comfortable, non-competetive pace?

Jesus we all need to work on our flexibility, god forbid one day I may delve into the arena of yoga you so advocate, but what if a shorter TT is more comfortable and aerodynamics not such an issue?