Question - what are the main things to look for in the way the pros swing?
Answer - They take the club back wide and high, then the downswing is inside out, and the follow thru ends with all the weight on the front foot. As strange as this might sound, Jim Furyk (the man with the loopiest backswing) executes this just fine, which proves the only purpose of the backswing is to arrive at a strong hitting position at the top, no matter how weird the backswing may look.