I have been hitting my irons with an in to out swing (I think), but the marks on the bottom of my driver, left by the tee, show a bad outside in swing with my driver. as well as an erratic contact point.(tee marks on the driver from toe to heal. I have always made, what appeared good contact, but had no distance. Just yesterday, I concentrated on a straight left arm through out the swing (as well as keeping it closer to my body), and was hitting the ball much farther, and the tee marks on the bottom of the driver were dead straight and more concentrated around the sweet spot. I was not hitting the ball any straighter (I have always hit it straight), but farther, and with what felt like less effort. Would a straight left arm have this much effect, or was I just "in the grove" yesterday? I was also hitting my irons much farther.