>With Greg Hiller's advice, I tried it. It killed everything including the corals. And now I'm hunting Greg for revenge.<
If you dip long enough, or multiple times with a concentrated solution, no question, you can kill corals.

Prior to finding out about Levamisole I used this on the Montipora eating nudi's that I found on a frag in one of my frag tanks. I found that if you take a coral out about once every 2-3 days and dip it in....geeze...cannot even remember the concentration exactly, I think it was about 30 drops of Betadine per liter of bath water, if you do this for maybe 3-4 times, and blast them with a powerhead or turkey baster toward the end of each treatment, you can get all the nudi's. I know I did!
It's probably a lot harder to do it effectively on large colonies, and particularly difficult I would imagine if you were trying to do it on large colonies and then returning them to the same tank. I know that Lugol's works as well, but it's just a more expensive chemical. You can buy a really large bottle of Betadine at the drug store for low $.
Both Lugol's and Betadine will also knock back Acro red bugs as a dip (tried these years ago when I wrote the article on these buggers), but they will not get them all the way that Interceptor does.
I have no idea if Lugol's or Betadine work on the Acro eating flatworms, I think from threads on the SPS forum on RC, they have not worked well.
It's a bummer that some Acros don't survive the Levamisole treatment (Liam's experience).
Liam,
For the Acros that died from Levamisole, were they already under shipping stress, or were they perfectly happy before the dip? Did you use an airstone in the bath to keep the water moving a bit?