That is interesting about the ASSA. I have never noticed that variation before.
I was suggesting modifying the top pin holes so that the tapered top pin would spring down and be stopped by the taper against the wall of the hole in the plug and not when it actually touched the bottom pin. To do this the top pin must be larger than the bottom pin holes. This might confuse bumping also as there might be a very small gap between the top and bottom pin.