Not sure how much that plays into it. Phil had one top ten going into last year's Masters. McDowell struggled last couple of tourneys but has 4 top tens this year.
Augusta fits Mickelson about as well as any golfer ever. McDowell, a shorter hitter on Tour needs to be on top of his game.
Mickelson has problems when his driver is off and his putter isn't working. Augusta is designed now for the bomber in mind. He has about 1 out on every tee shot at Augusta. Augusta is much more about hitting shots close from long range approaches than it is putting. You're just not going to make a lot putts at Augusta from 25+ feet. And because the greens are so slick there, if you're hitting greens there but leaving yourself with 25+ foot putts, you're more likely to 3-putt. So the guys that have an advantage over Phil with putting...probably have much less of an advantage unless they can hit shots close. But, for all of his ballstriking woes, Phil is consistently one of the best on Tour from long range (175-225 yards). And because he hits it so long and doesn't have to worry about trouble at Augusta (vs. a place like Pebble), he can avoid those long range approaches as well, while somebody like Kuchar will have more of those shots.
And Phil works it right to left which suits many of the doglegs.
He's finished outside the top 10 *once* in his last 11 Masters Tournaments.
McDowell has played August 3 times, missing the cut twice and finishing 17th in '09.
But my point is that a guy like McDowell probably has to go into the Masters playing really well because the course doesn't suit him nearly as well as it does guys like Phil, Bubba, D. Johnson, etc.
3JACK