I just noticed the other issue you created, listed at 4 hours. Would that trump this one? If so, I would want to switch the sponsorship over to that one

The 2 issues are related, but complementary, although they both improve performance in different ways.

This one is quicker for me to implement and also a bit more useful because it means you won't get so much noise in the editable list of categories to look at (i.e. categories that haven't had new content in ages won't be shown).

okay, if both need to be done to accomplish the goal, let's do both