im sure i remember my father setting fire to a load of wire years ago, and i think it melted it off a treat.
I use methylene chloride to strip PVC insulation, for twin & earth I use the earth wire to split the outer sheath and coil the live & neutral and dunk it in Meth Chloride for a few hours. The insulation turns to jelly and I just run it off with gloved hand.
You must cover meth chloride with a layer of water to stop it evaporating, and wear face/eye protection.
Cheers. I want to see if I can flat the scratches on some polycarb guarding with fine wet&dry then chemically polish it with methylene chloride to restore the optical clarity.