The ultimate first world problem? I'm happy with the old electric can opener I inherited from my parents. It's just about worn out and if it balks I use the equally ancient Ecko (K-Mart cheap) clamp on and twist the knob can opener.

As to P-38, back when we had out of date C-rats in training, first thing was to go to the PX and get one of those stainless pocket knives with a decent can opener.

[Linked Image from specshop.pl]

The key elements in human thinking are not numbers but labels of fuzzy sets. -- L. Zadeh

Which explains a lot.