Funny story I heard on TV

CBS Sunday Morning did a profile of James Carville and Mary Matalin. He is so hyper that he says one day a doctor approached him at an airport and said "I've been watching you for 5 minutes and I think you have ADHD." He got diagnosed and treated and it improved his marriage a lot. If strangers can see it, why can't the ADDer him/herself see it, or their spouse?