CTE is not just about concussions but any amount of damage consistently over time that accrues.

Current line of scrimmage situation is the worst case scenario. Linemen are a couple feet away from each other and they start from a crouched position. They explode up and hit the opposing line, very often with their helmet/crown, down after down, 60-70 times a game. You could not plan a better way to get CTE.

1) Neutral zone at the line, they start 2 yards away from each other.

2) Have to start from standing position, and/or:

3) First contact has to be arms

It would be a bit of an adjustment like it was for dynamic kickoff. You're never going to stop all head trauma in a contact sport but the mechanics of the line positions are basically designed for it.

Not the OP but I don't think you can. The issue is you're stopping a moving object with your body. That is always going to cause damage. I think the armor itself also promotes big hits. I truly think that's the reason Rugby is a safer game; the hits are more painful, and you're not hitting each other with a carbon fiber helmet.