How many baseballs bounced off of his head? Was he that bad a fielder? Was this the head ball era? I think the UK folks who wrote this paper might not understand that getting a ball in the head is not a common occurrence, like oh, say, being tackled is in football. I think that the point about misdiagnised football players is believable, but once again science diminishes potentially useful results with overreach. Did I miss something here?