I know that they’ve found in racing that stiffer padding is better.
I understand what you are saying, but the racing/football comparison is a bit hard to make, since the helmets and protective gear in racing are there for accidents, not as a regular part of the game, as they are in football.
I think the hans device has helped. But simple physics shows that when you have forward momentum and stop suddenly, the jello like brain still moves forward. Look at Terry Bradshaw. He has problems with depression and is damn near retarded.