Back to tapered-bore engines; the pinch does not exist, when the engine is running at its normal operating temperature, so no vibrations will be caused by this 'cold only' pinch, neither will any additional wear take place.
When it is broken in perhaps, although I am not convinced that all engines have the proper taper to be straight at operating temperature. I have had many engines that would not idle smooth during break in and would stop with the piston near TDC when idled low. They will also shake, but this goes away when broken in.