I've had a saddleback Valentini for about 7 months in what is supposed to be a FOWLR. But whenever I break off a piece of coral in my main tank ( either as part of pruning or by accident), I often stick the frag in my puffer tank. She occassionally knocks things off of rocks (I don't glu things in this tank), but hasn't eaten anything.
I have frags of SPS (montis and birdsnest), LPS (frogspawn), and softies (leathers and 'shrooms). So all kind of weed-like corals. I wouldn't care if she did eat them, but it makes the tank a little more interesting than just having piles of rocks and one fish.