After reading the RS thread It seems like it would be better to dip the rocks you want to kill softies on and then place the rock in a QT and run carbon and do water changes before returning the piece to the display. I don't understand why so many people returned the dipped colonies back to the display immediately. Some even said they removed GSP and Leathers until the display was purged of the fluke tabs.
Using Fluke Tabs seems like a last ditch effort to kill AEFW's, some soft corals and GSP.
I do have a soft coral similar to GSP but it just looks like grass when extended and like a plucked chicken when retracted. It's nearly impossible to scrape off the rock so I may try dipping it and placing the rock in a QT for a month or so before returning it to the display.