IME dwarfs are likely to nip at fleshy stuff. I don't keep LPS like brains, favias or Acans. None of my angels have ever touched frogspawn, hammers, torches or Duncans. Certain species are more of a dice roll. Next months speaker can speak to the order of least likely to most likely. Current dwarfs are a potters and a flame. They have nipped Jedi Mind trick, no other monti's????
Large angels are known to be the ones that can devolop a taste for softies and LPS. The only ones I have tried are the majestic and haven't had that issue yet. Currently have one majestic.
I also have genicanthus and those are widely considered reef safe. My genicanthus angels have always been "angels" :lolspin: currently have three wantanabei.
All fish added to my system go in the frag tank before the DT. They are easier to remove/ isolate if they have an obvious taste for coral.
The nipping I have experienced is that the coral stays retracted and slowly declines (to malnutrition I assume). Never had a angel damage the flesh of the coral. I understand the fish is interested more in the defensive slime than the flesh of the coral.
Hope this helps!