Unfortunately I'm jumping on the bandwagon too with a couple corals. One I got last October at the frag swap - went to work yesterday and it looked fine, got home and it was almost all gone. All the original tissue is dead, just some of the new encrusting tissue is alive. This seems somewhat odd since RTN often starts at the base and works its way up. The other is a new release from JF that I got in March. Its demise wasn't as rapid, but same story - only a little of the new encrusting tissue may still be alive.
I followed Andre's procedure today and we'll see what happens.
I'm guessing the stressor in my case is the dino nightmare that has taken over the tank. It has even killed my Xenia.