"measuring helmet g-forces is a proxy to find head g-forces but they are not one and the same" I don't think I said they were, just that it's a worthwhile thin

"measuring helmet g-forces is a proxy to find head g-forces but they are not one and the same" I don't think I said they were, just that it's a worthwhile thing to measure to see if you should start finding a way to get better measurements. I agree they are not the same and this is not a definitive study. This is often how science works, you do something quick and easy. If it came out that it was only ever minor forces on the outside of the helmet, it's probably not worth investigating since the forces inside the helmet will be even less. If they're huge, repeated forces, it's probably worth trying to come up with a better rig to measure actual force and see if it's above a healthy level.