I was just having a little fun.

Since you work in a shop, it'll probably happen somewhat frequently. If you randomly grab one of the cells, odds are that each will get used fairly evenly.
I don't bother trying to "switch spots" either. IF it even matters in a serial device, just the randomness of just putting them in ensures a fairly even occurrence that they will be taking turns in both slots.
I label mine A1, A2. B1, B2. C1, C2. etc. I just make sure I grab two of the same letter when one of the dual batt mods needs freshies.
Wish I had done that with my AW IMR's. Not for marriage, just so I knew which ones were the oldest. I guess I need some kind of device to measure their capacity or something, as my oldest are about 3 years old and my newest about 1 year old. However, there doesn't seem to be a noticeable difference in the drain time.