How about Cyril and Mary both play the trumpet. That way there is no need to even consider a comma.
When Mark Lovewell and I thought our book Songs of South Street . . . was ready for publication we took it to an editor and she showed us how much better it read with about 2/3 of the commas removed. We learned a lot about cleaning up grammar from her. That was in ye olde days before word processors and easily accessible computers. A lot of retyping but worth it.