Try riding around on a bmx for a while and experience the handling when traversing through city streets. It's pretty quick. True, hand positions on a set of riser bars can be approximated with any number of bar/stem combinations, but the possible placebo effect of having these on my bike cannot be overstated. And I'm not sure it really is a placebo effect. If anyones' got a study done on the handling of risers v.s. other bars, post up That said, I ride around with bullhorns because I do have to climb a fair bit on my daily commute.

edit - And not that I have any experience with them, but don't they block the streets off for crits? You don't go through the bumper to bumper car traffic, pedestrians, etc. It's still a race, not the unpredictable, day-to-day obstacle course of city traffic. I'm kinda talkin outta my ass on this though.