That's the stuff. But my query is whether I need it? I can't see what it does apart from melt.. it doesn't seem any more heatproof than the cable itself and all it does it make the cable hotter by getting hot/melty itself and being in close proximity?
No idea, but that crinkly plastic stuff usually goes brittle with time and heat cycles. The cables are are consumables as time and heat cycles make the cables go hard and fail.
Some people wrap the HT cables with tin foil to help heat dissipation but no idea if it works.
That's the stuff. But my query is whether I need it? I can't see what it does apart from melt.. it doesn't seem any more heatproof than the cable itself and all it does it make the cable hotter by getting hot/melty itself and being in close proximity?