I am rating Tiger's performance at the President's Cup based strictly on his performance in relation to his capability. He is the greatest golfer, but absolutely under performs in the Ryder and President's Cup.

I think Phil finally looked comfortable in the leaders role this week, but Tiger just does not take a team on his back like Jack and Arnie used to. It may be the last thing on Tiger's career where he does not compare well with Arnie and Jack. His record playing with others and alone is not indicative of the greatest golfer on earth (which he is). In fact, on Sunday, he played a little better than average striking the ball, but could not sink a putt.

What causes him to stink (comparatively) at these events?

I think he is trying to keep emotion out of his game, but also wants to get emotional about playing for his country, and this internal fight throws him off. He should play as if the other player said something overnight and needs to learn a lesson. Just my thoughts.