I ran a separate coax run to all my possible sub locations in the room that I never seem to finish. You can get very tidy 6 connector wall plates to terminate them on then just plug into whichever one you need. Should I ever actually run two subs, the splitter will be between the AVR and the wall plate.

Loops of coax to multiple boxes make for a bit more complexity to troubleshoot in the future should something funny happen. Because coax is so dirt cheap, I was thinking more about simplicity than I was concerned about electrical properties.

With great power comes Awesome irresponsibility.