== Grouped as == 

 I inserted the word "usually" before "grouped as either (3+2) or (2+3)" although I'm not sure that's what I meant either. Many of the orchestral works listed, at least, have no indication in the notation that they are intended to be subdivided, and I think we are talking about the natural human reaction to look for a subdivision in the rhythm. So, yes, it's hard to listen to Mars without thinking of 3+2, although I believe there is a recording where the conductor is thinking 2+3. The Tchaikovsky could go either way, or different ways in different measures. But would we say "4/4, subdivided as 2+2"? I didn't give the same attention to the other entries (7/8 et al) although they probably need checking. Thoughts?