Man, I foreseen this question... and NO I don't. I can tell you that I have numerous Brett Hull autographs... and in comparing the signature, its LEGIT... I hope that doesn't discourage you from bidding, but if so, I can understand. But I'm quite confident its for REAL. As a St Louis native...
Auto looks good. Brett Hull is one of the best signers in sports. He signs everything you send him TTM. Not to go on a rant here, but COA's are absolutely worthless. I've bought several autos that came with COA's that were fake. COA's are no more than a piece of paper...don't prove that its authentic. Every autograph I see posted up here, there is always someone asking if it comes with a COA...just trying to educate. I've been collecting autos for about 15 years now...been burned a couple of times and learned my lesson :)
You're absolutely right... COA's are worthless... the only true authentication is when a card company puts their seal on it... Upper Deck, Stadium Club, Fleer, Topps... and so on. ;)