of the printing (could be quality control) but with respect to edge printing, by Chipco, when a chip has different designs on each side... You can expect a fifty/fifty mix of orientation. As I understand the Chipco process, printing to the round surfaces (both sides) happens at the same time, while printing to the edge (sometimes called "rolling surface") is done separately.

I don't know if separately means before or after the front/backs are printed, but they are done without regard to orientation. Statisically, the mix will be 50/50. Unfortunately for people like me, I will collect both versions (as a variation!) when possible!

BTW-This is a bit similar to chips with different front/backs and an insert pattern that reverses when the chip is flipped over.

Jim