Yes, but it usually doesn't help much. The sounds they use are generally pretty even. You can get it punchier, but you risk loosing what little dynamics the machine has. It definately worth a try, though, and works great on some tunes.
Its a godsend at times if you have a drum part programmed in that's *too* dynamic- a compressor will help take that excessively loud hit. Easier than reprogramming the part.
Take care,
Chris