With regards to the interpreter knowing when a lexical is no longer used ... I have no idea. Anyone know?
With regards to the memory consumption of classes/methods created on the fly ... I thought that it would use more RAM. However, I didn't test it, so I don't know. It would be an interesting thing to benchmark. I would think that it would take more CPU, though. However, I don't know for sure. It's more of a hunch that anything else.
/me wants to be the brightest bulb in the chandelier!
Vote paco for President!