Correct.

I've hit 40 in my 52/12 but this wasn't an hour into my ride yet, so I doubt I can sprint that fast at the end of a road race. Plus I'm now equipped with a 52/14, and the max I've gone was about 37...again it was early in my ride.

And 40mph isn't a sprint yet for a pro, unless maybe there is a slight incline or a headwind. I think Mark Cavendish crashed (Stage 4, Tour de Suisse 2010) at around 50mph because that's what i remember hearing from the commentary.

And if you still need proof, take a look a Tyler Farrar's sprint.

Note: 78km/h= 48.5 mp/h