I split your original post into a new topic so that people would find it.
To answer your question: soft corals are real easy to propagate. Todd Crail did an excellent job outlining what it takes to propagate corals here: http://reefs.org/library/farmertodd/ Check out the Tools section and the Fragmentation: Softies section. Nepthea would be the subsection you should refer to.
Most of the soft corals are incredibly resilient to fragging. Most of the time you can just slice off a branch with a razor blade and superglue it to a piece of rubble and that's it.
With all of my softies I cut of a piece with a sharp razor blade and rubberband lightly to a piece of rubble. The only thing I have not had sucess with is colt.
Kenya Tree (capnella) produces so many babies for us that I've never considered cutting it. Little pieces routinely disattach and end up all over the tanks--requires occassional "weeding". Other softies (Colt, Sinularia, etc) I've cut many times and never had a problem.
I agree with everything stated above. I actually just sliced off a good sized branch from my ever growing tree and the Frag has now attached it slef to the new rock only like 5 days later.
Good luck.
Mine drops an average of 5-10 babies a month on its own! It will kind of constrict and pinch off a branch and it will then float and settle to a new area in the tank. I have 2 different variants in my 215 and I am thinking of taking them out because they grow so damn fast - worse than xenia by far but they are pretty.