Thanks appreciate it. Yes the amount of loft effects how much the face contributes to start line, again in that 85-75% range (except for putters and some wedge shots). In figuring out how much to aim right, you basically just try to aim where you want the ball to start. So let's say for a 7 iron shot, you aim the face 5 yards right of the flag to accommodate for a 3-5 yard draw. If the ball starts where you want it to and over draws(left of the flag), then you had too much path, if it was a straight push, the path and face were about equal.
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