It can be...but it is a long and (imo
) dangerous (for the coral) process. You would start by sawing the bottom of the skeleton a little once per week. When there is just a sliver of skeleton left you very gently break it and let it's own weight do the rest of the fragging. I think fragging non-branching LPS
has to high an infection rate for me to try. However...I have seen some Fox corals where there were seperate polyps on the same skeleton. These would be quite easy to frag, by cutting the skeleton between the polyps (similar to branching corals).