umm, what?
the geometry between many trek and lemond models is almost identical, with the traditional flat top tube (not sloped like Specialized). compare a trek 1500 or 2100 to the same priced aluminum lemond models with 105 components on them. you'll find the seat tube, top tube, and head tube lengths to be nearly identical, except that lemonds come in odd sizes (55, 57, 59) instead of 54, 56, 58, 60 cm.
Not identical. Close, but "close" fit on a road bike isn't "fit".
Lemonds, at that price, have compact geometry. relative to their incrementally longer effective TT (IE 57 Lemond fits more like a 58 Trek) and slacker (by one degree) Seat-Tube, giving a longer-torsoed rider a better fit. This Same 57 fits in between a Specialized 56 and 58 as far as top-tube lengths go.
This 57 Lemond, also for example, has 23 cm more standover that the shorter Trek 58.
So, that is why. We all know they are made in the same factory, but they are not the same bike. The only real reason to buy a Trek anyways is cause Lance rides one, didnt you know that? Jeez.