I'm pleased to see how pertanent this thread is to the Road Cycling forum... nice.
Tell me, why is this interesting?
Is this supposed to be a factor in cycling fit or something to that effect?
After the length of your legs, this is the most important factor in bicycle fit.
It really is amazing that so few people know this. I think it's also probably the reason so many road cyclists complain of upper-body discomfort (hands, wrists, neck, shoulders, back etc).
Here's someone with average flexibility for a pro cyclist.
If you can do that, then you can have a seat
tip to bar drop around 3 inches. If not, you're asking for some serious discomfort.