Ross Jul 23, 2014
The angle varies depending on the club and desired shot. First, you want to always make impact with the shaft in a straight line with the front arm! Sometimes you want to meet the ball at the bottom of the swing arc (hybrids, fairway woods etc.). Sometimes you want to meet the ball just before the bottom of the swing arc (Sand Wedge). Learning to setup takes many hours, weeks, years of practice. There is no exact (works for everyone, every club, setup). You have to put in the time and gain the experience to know what works best for your needs.
Yes the back arm can bend, but it is the elbows staying towards each other that is important. Now, the wrists or hinging is something that has been changing over the last year or so… please read this: To Hinge or Not to Hinge
I think that beginners with my method can speed up the process learning to turn and use the body, if they learn to have no or very little hinging. If you hinge, you’ll have to “un-hinge” during the downswing and when you do, the body will stop turning to let the hands throw the club… so, remove the hinge so you can learn to turn and know how it feels and works, then put the hinge back in if you think it helps… I have my doubts