[galopin]

Can you have your hands too far forward at impact? What are the possible pitfalls of being in such a position?

Three problems that I can think of:

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.