Posted by: craw
If the published ESTA is the same across sizes then it's probably measured at the seat collar. Which means that for an XL rider it's much much slacker than that at pedaling height. It's like they resisted modernizing their geo for so long and now they've delivered half measures.
If you look at their geometry diagram, it looks as though they measure STA at the intersection of a line drawn up from the BB, passing the back of the ST and intersecting with the reach line if it were extended back beyond the stack/reach intersection. Since the BB is a fair distance behind the ST, this gives a pretty bad indication of what the actual STA will be.