Mike's 7 millis are as hairy as Chewbacca despite the 20ish fish he has in his tank. He must have accidentally picked the select few millis that have extending polyps.
Very true, combining fish that think millis are tasty with millis in the same tank could possibly result in unhappy millis that take their polyps and go home.
It's very true that Mike chooses his fish carefully. Ones that nosh on his corals aren't welcome. Otherwise reef safe fish that didn't get the memo are quickly evicted. Sometimes forcefully.
Strangely enough, I'm pretty picky about my fish, too.