This was a crit my junior son was in Sunday. He was a few seconds behind the crash. Watch it in full screen/slow mo and see the front hub within inches of the rider on the ground's - neck. Would a disc have cut his neck? Unlikely, and it was not one of the 8+ discs in the race. But likely enough that I don't want to find out. There was a team with discs. Not really worth the risk IMO.