True story:
when moving rocks in my tank, I didn't realize that my green leather had started to attach to another rock, and just "yanked" it up, RIPPING the leather right down the middle, from top to base. Let me repeat, I RIPPED IT in half, not cut.
While I do NOT recommend this at all, both sides recovered perfectly and continued growing with no problems at all.
Leather corals are VERY forgiving! lol