I suppose I take a neutral stance on this. I don't necessarily think anything bad will happen, but I don't think anyone should be claiming "nothing" will happen either. It has never been done before, so claiming that you know what will or wont happen is pointless.

I think that, with the POSSIBILITY of what could happen, it isn't worth doing. However, they won't just stop because of that. Hell, the guys working on the Manhattan project were probably pissing themselves the first time they set off the chain reaction, thinking it might go on forever.

But why take the risk?