While I applaud the logic in saying that the post drilling wet 
     processes only expose the problem and are not the cause, I believe the 
     logic should be taken one step farther. If you look at the drilling 
     process, it is difficult to visualize a .0135" diameter drill (that 
     will break if you look at it cross-eyed) pulling layers apart. 
     Consider also that the stack is clamped with a pressure foot before 
     the drill touches the stack. I believe that drilling is very seldom 
     the cause, rather it plays almost the same role as the post drilling 
     wet processes by exposing the layer to layer join in the hole wall. 
     Also, my experience has been that wedge voids and pink ring will 
     happen on only one layer (possibly two) and not on the others in the 
     same panel. Again, it's difficult to imagine a drill bit selectively 
     wedge voiding a hole wall at one specific point in the panel 
     especially when the drilling takes place in a two or three high stack.

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