I too have experience with having a limb in a cast (and being cut out of it - on two separate occasions). The answer to your question is - it's a good idea except this situation is not quite the same. I don't know about your cast, but each of mine were made from plaster, not steel meant to stop bullets (the S.D.C. equivalent of a Mega-suit, right?).Hey Dann, I know from personal experience that the cutters used in removing a cast from a broken bone don't cut skin. When I was ten I broke my arm, and when the doc took the cast off, he showed me that it would make a bit of noise but not hurt me in any way. It used a vibrating blade that actually kinda tickled on my skin.
Do we have any idea if something like this might work on the armor?
The Mega-damage version of the device used to free us from our casts does not exist in Robotech: Broadsword. Hence the real need for the Wild Cards to find a different solution.
Notice that Hercules is pretty specific about using a blade that does not vibrate? That might be for reasons we could ask Captain Hesperus about. Whaddya say, Cap'n? Why no vibrations in the cutting tool and why no heat? =)