Bounce calculation

I believe it is a simple subtraction. You'd lose 2 degrees of bounce, likewise gain 2 degrees if going in the opposite direction.
 
That's correct.
I think you'll also reduce any offset by a small amount.
It could alter the way the bounce and grind work but it should be easy enough to bend it back should things go haywire...
 
I depends on how much you have in the first place

I have a number of 52 wedges they range from -1 to +12

However assuming you mean bending a club you would hardly notice the difference in play between a 48 and a 50 and that assumes you mean the same make a type of club.
 
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