There are almost constant rule changes around the tackle laws, the breakdown and de-powering the scrum to reduce the amount of potential head trauma, but the pr

There are almost constant rule changes around the tackle laws, the breakdown and de-powering the scrum to reduce the amount of potential head trauma, but the professional era it's like an arms race. Even padding and head-gear, players seem to hit with even more force. And, like the article says, a lot of the concussions happen during the training sessions which is way more than the average amateur player would experience. It's still relatively soon to see the longer-term effects; the early batch of professionals from the mid/late 90s will soon be entering their 60s and I expect there will be more research papers..