Where do you use Smalltalk?

This question was asked recently at http://stackoverflow.com/questions

I love the responses that say, "It's great. But only use it with good developers that do unit testing."

Why would you use anything with any other kind of developer? And is the claim there is a tool that actually _works_ in those situations?

BTW this is not a new kind of comment from people. It just never ceases to amaze me that those follow-up questions neither seem to be asked nor answered.