This is a more detailed article that includes a couple of quotes about Dr. Carrick's methods (short version: doctors are skeptical):

http://www.theglobeandmail.com/sport...rticle2268854/

After observing the situation for a while, I am going to make a prediction (this is pure guesswork): Crosby is going to retire from hockey. Maybe not in the next few weeks or months, but I think it's going to happen before too long. If he is having a recurrence of symptoms this early on in his return to play, it does not bode well. Hockey is a fast, physical, at times violent sport. He's going to get hit again, often, and at times very hard. Head impacts are a virtual certainty. Infinitely better to get off the ice now, when he has a good probability of making a strong recovery again. He can have a great life without playing hockey; he's just going to have to make an (admittedly huge) adjustment. Either way, I wish him all the best.