I certainly would have, had I suggested the problem trivial! I'll keep that in mind for if I suggest things are trivial rather than suggesting I lack understanding.

> You also can't generally "and so on" constrained combinatorial arrangements like this.

I know you can't generally but in the specific case I proposed you can (3 sets of 3, 4 sets of 4, 5 sets of 5, each dice taking one ordinal of each set).

You might want to check that your proposed generalization criticism applies to the generalization at all before suggesting the arrangement doesn't work :)

Saying “I'm having trouble understanding” is not the same thing as “this is trivial”.