petera - you are right. Surprised myself, but there it is. Maths...

petera - you are right. Surprised myself, but there it is. Maths aside, it would be tragic if it happened. Mickelson doesn't deserve to be in front of Tiger.

http://www3.signonsandiego.com/stories/2009/apr/07/golf-masters-notes-mickelson-win-no-1-738/

It appears to be a little easier than Tiger missing the cut if Mickelson wins. According to that article at least, if Mickelson wins and Tiger is outside the top 5, then No.1 is surrendered.

McIlroy - top 5 finish.
Kim - top 5 finish.
Ogilvy - each way.
Tiger to win.