Hmm, perhaps I was not clear. Given the choice between going over the top of handlebars versus the top of a vehicle or grill, I believe the difference between the handlebars and vehicle/grill is much larger than the difference between vehicle and grill.
Given the choice of hitting an inclined windshield and rolling over the top of a vehicle vs. taking the full force of a giant body-length grille, I'd rather take my chances with the windshield.