1. Arching the Left Wrist opens the Clubface. So if you set up your Alignments with a Flat Left Wrist, and at Impact you have a Arched Left Wrist, the Clubface will be more open and the Ball will start Right. There are two ways to correct this:
a) set up your Alignments at Impact Fix with an Arched Left Wrist.
b) set up at Fix with a Flat Left Wrist and increase the Roll of your Left Hand/Arm in order to have the Clubface square by Separation.
2. Both Bending and Arching the Left Wrist shorten the radius of the Stroke, and therefore reduce Clubhead speed. The radius is the distance from the Left Shoulder to the Clubhead. For example, if you shorten the radius by an inch because of Bending or Arching your Left Wrist, that is effectively the same as reducing the lengths of your Clubshafts by an inch (i.e. putting a nine iron-length Clubshaft into a seven iron Clubhead). You maximize radius with a straight Left Arm and a Flat Left Wrist.
3. Both Arching and Bending your Left Wrist change the Fulcrum and thus, the Low Point of the Stroke. When your Left Wrist is Flat, the Left Shoulder is both the Fulcrum and Low Point; when your Left Wrist is Arched, it becomes both Fulcrum and Low Point, and causes the Low Point to move forward of the Left Shoulder (a Bent Left Wrist causes the Low Point to move aft of the Left Shoulder).
Note: I should've read CNZ's post before I posted. He pretty much answered the question.
My best wild guess would be to find where in the Stroke that you Arch the Left Wrist (at Impact Fix? Start Up? Back Stroke? Release Point? Someplace else?).
When you hit a chip, and take the Stroke to Follow-Through, is your Left Wrist Arched or Flat? If it's Arched, you should practice hitting chips and make sure that your Left Wrist is Flat from Address* to the end of the Back Stroke (for a chip) to Follow- Through. Keep in mind that when the Left Wrist is Flat, the Clubshaft is in-line with the Left Arm (from the front view facing the Player). So hold your finish at Follow-Through and check for your Flat Left Wrist and an in-line Clubshaft.
Then do the same for pitches...that is, check to see what Left Wrist Alignment you have at Follow-Through. Then do the same thing for full shots...take them to Follow-Through, hold this position, and check your Alignments.
I don't see a need to go any farther than Follow Through, because after Follow Through, you Swivel, and the Left Wrist moves from Flat to Bent (as the Right Wrist moves from Bent to Flat) in order to keep the Clubface on Plane.
Good luck.
*If you're hitting Swinging chips/pitches/fullshots, you can start from a Bent Left Wrist at Adjusted Address, but check for a Flat Left Wrist at the end of the chip/pitch/full shot Back Stroke.
I just thought of something that I didn't mention in my previous reply to you. As I said above, Bending and Arching the Left Wrist shortens the radius of the Stroke. One reason why you may be Arching your Left Wrist is to shorten your Stroke's radius in order to compensate for Bobbing--dipping your Head below where it was at Impact Fix.
I just thought of something that I didn't mention in my previous reply to you. As I said above, Bending and Arching the Left Wrist shortens the radius of the Stroke. One reason why you may be Arching your Left Wrist is to shorten your Stroke's radius in order to compensate for Bobbing--dipping your Head below where it was at Impact Fix.
Hadn't thought of the that one! Thanks for all the great input!