Here was my conumdrum looking at buying a Surly Troll--and wanting to put dropbars on it.

I tend to be comfortable on a ett 55 ish cm toptube bike for dropbars, more or less a medium frame. On paper, a med troll has a ett of 596mm, and a small 571.

Well, a small must be right right?
The more I thought about it, it didnt make sense for a 5'10 guy to be on a small frame, and ended up getting the medium and using a short stem (55 or 60mm) as well as drop bars that are not very "long" (distance from tops to where hoods are, and yes, diff bars have diff dimensions, which makes a diff)

bottom line, is that on paper, the troll didnt make sense, and I figure its because it was designed for mtn bike bars, ie with sweepback, and then of course they ended up selling them with Jones bars, which REALLY come back towards the rider.

so bar choice is a factor, and despite working around the oddness of a troll frame, a short stem works and the bike handles wonderfully, even fully loaded.