I do have to disagree somewhat. Yes, some of it is marketing, but altering trail, chainstay length wheelbase etc does make a difference. Of course both (yes, I know that there are more than 2) of geometries can be raced and won, but they have a slightly different feel. There is also fit. I can fit any race style geometry and often buy a bike w/o bothering to ride it, but would have a very difficult time making a bike with a tall headtube fit me. It would fit, but I am very flexible and am more comfortable with a ton of saddle to handlebar drop, which I could not match on a roubaix, z series or blah blah.