The sides of the helmets have been shown to be the weak link, and where most of the concussion come from. (no statistics, just from memory of all the talk)
Plus there is also the slow down phase. How fast the brain goes forward is dictated by the stopping power *speed* on the other end. Slowing it down works, think of a gymnastic mat. That's why some people like Don Bebe have that cushion on the outside.
My point being, that our current helmets probably look FAR differently from the IDEAL ones. But when they 'think' of a new one, they use the old one (and all its flaws) as the base model.
That's groupthink, and someone needs to get through some thick skulls to address it.
But yes, at some point the body has limits. But I think we can take a step or two back, and I do like what the league does now with concussions, which coupled with a better helmet would probably do a reasonable job of stopping this.
Plus whatever the NFL sets as standard, the industry will. Meaning the pop warner/high school kids playing now (who also get concussions....who then might get more in college...then in pros) will get better equipment and have more 'billy bob' hits left on the meter.
The NFL MUST protect it's future employees, and it can do that by changing the dynamic of the helmet. This is a private business. But at some point, private businesses tend to screw up. If they don't want the gov't getting involved, then they should get to work on this in earnest. They need to quit nickel and dime-ing it. It's quite obvious they haven't done what they should, and they still have a chance. But this is a real problem, and if the NFL (see business) doesn't do what it needs to, and this IS a need, then govt MUST come in. NFL....you are on the clock.