Guess I should have mentioned that for loose tenons I make the "tenon side" mortise fit snuggly and the mortise side with a little wiggle room. I usually use a Domino and set the mortise width to the narrow (actual) width of the domino tenon. For the mortise side, I place the hairline cursor just on the outside of my mark, plunge, then place it on the other side of the mark and plunge. This still gives me a little wiggle room, but not a sloppy joint. I don't like setting the width of the mortise to the middle or wide settings except for shelves, etc.