Dave, I've been following a few threads around frame geometry and specifically ST angles. Searching the web brings up all sorts of posts from people trying to get their saddles far enough back. It also seems to me, watching the TdF in recent years, that there is more of a trend for saddles to be lower and further back. Looking at some of the detailed bike specs there are some serious lay back seatposts in use.
I think I understand the theory behind using smaller frames and long stems around handling, weight, etc...not saying I go with them though. But I'd be curious to know if there is some sort of advantage/disadvantage around seat tube angles and seatpost setbacks? For example:-
I have my saddle top about 79cm from the centre of the BB and I find, at this height, that each degree of ST angle equates to 10mm of fore/aft position. So using a Brooks saddle all the way back, on a 71 deg ST with an inline seatpost, to replicate this position on a 73 degree ST I'd need 20mm of layback on the seatpost...roughly, my trig isn't the best.
I'd be really interested to hear your views on this area?