I remember grinding up Mt Evans, The Tour de Gila, Tour of Utah, etc 53/39 and 11-25 on steep days and 11-23 most days. I even thought I was "spinning". Turns out I was just young and strong.
I ride 50/34 x 12-30 now. I'm slower but it's not because of the bike. I really would like to take the gears I've got now and apply to the fitness I had at 25.
Yes, I'd regularly hit 50's. I think the most I recorded was 58. Pretty sure I wasn't pedaling any of those times.
Trek aren't dummies. How many top pro's are riding sustained speeds where 50x11 just doesn't cut it?