I'm skeptical that this will make a difference. We have very little knowledge about repetitive trauma to the brain and chronic brain injury. All a neurologist will be able to say after a concussion is that the player is back to his/her steady state. There is little data to inform whether or not a second, third, fourth, etc. traumatic event to the head will lead to chronic problems.
Until we understand this topic, doctors will not be able to adequately advise patients (players) as to their long-term risk.