Originally Posted by Metzinger

As penance, I'll try to think of some actual reasons for wanting a non-slopey top tube.

1. More space for a shoulder carry cyclo-cross style.
2. Proper tube angle for one of those inside-the-frame bags.
3. In the case of smaller frames, enough room for a full sized water bottle in the seat tube cage.
4. Old school aesthetics.

How's that?