It would seem to me variation in the diameter of an inlaid piece of paper would require different dies. This is a process change, not a process variation. I would say chips with two different size inlays are different varieties. If you find chips with 10 different inlay sizes, you are seeing process variations (like color differences).

Mis-registered color printing can cause different appearing designs, but I fail to see how or why this would change the diameter of a die-cut inlay.