So are you suggesting there is no possible chance of it ending badly?
1. I pretty much only deal with "healthy" clowns. If you're starting with a sick clownfish, you have a whole different set of problems.
2. I would only do it with a BTA or a Ritteri. Carpets are the only anemone that in my years of doing this seen eat clowns. (Hosting Anemones.. I think Rock, Condi's, tube, etc. are all very capable of eating clowns also)
3. I'm saying that if start with a healthy fish and health anemone, I don't believe there's a chance of killing of the fish.
So, I suppose that in a very stupid situation, you might be able to kill the clown fish....but if it's healthy, I doubt it.