Given the situation, I don't think anything really has changed. Again, you just have to look for "effective top tube" with the compacts.


It is, but my recollection is that road bikes have largely settled on the 72º-74º range for seat tube angles. (E.g. the seat tube angle on the Roubaix and Tarmac are nearly identical.) And a 0.5º difference over 580mm only results in a 5mm difference.

I think you'll see a lot more variation with head tube height, trail, wheelbase and the like than seat tube angle, and you'd only see something like a 77º ST on a dedicated TT bike.

I'd think that if he needs a radically non-standard seat tube angle, that's going to alter his weight distribution on the bike, and you're almost certainly back in Custom Geometry Land to really get everything right.