By Tom Blow Padraig Harrington showed why he’s a three-time major champion on Thursday by playing an incredible recovery shot at the Houston Open. Harrington, 52, looked certain to drop at least a shot when his drive at the par-five 16th flew off to the left and landed under a bush. Many golfers wouldn’t even attempted to play a recovery shot from such a dire position, but the veteran is no ordinary player. Harrington got down on his knees and pinged the ball out from under the bush. His shot avoided the tree nearby and rolled into a decent position on the fairway, leaving PGA Tour fans in awe…