On the Vince Young comparison:
Based on a talk Bob McNair gave in Houston several years ago, he said that when the Texans were possibly going to draft Vince, they had him do a test where they put glasses over his eyes which distort your vision. They then had him try to hit a target with a football with the distorted vision. After failing several times, Vince threw off the glasses, and stormed out of the room frustrated that he couldn't do it. The test of course, was not to test his accuracy, but to test how he reacted to failing at something. He did not pass the test and that was part of the reason the Texans passed on him. Fast forward to the day he threw his shoulder pads into the stands, or when he ran off and nobody could find him and you see that the same behavior carried forward into the NFL.
If the story is true about how mad Johnny gets when failing at golf, we potentially have a similar situation with Johnny. I will be very interested to see how he reacts if he does not play well. It's easier to handle pressure when everything is going well, it is not so easy when adversity strikes.