My understanding is that when fragging rics, for best chances of survival, you MUST have part of the mouth in the pieces being fragged "cut it right down the middle". The couple times I've done this I've had great results, and within 15 minutes they have pulled themselves around a sealed the wound shut. If your looking to sell the frag, I say do it, if you just looking to get more for yourself, I say target feed to get it to split naturally.