Not at all, edexlab. I mentioned chopping through live cables only to make a point about tool durability, in that, I've cut through the odd live cable in my time (believing they weren't live) and, as you'll know, it's a sure way of causing damage to cutters. On the other hand, I've never 'deliberately' tried to cut anything I knew was a harder material than the cutters. Hence, as long as I'm not chopping through live stuff my cutters last for eons.
Whenever someone else cuts through a live wire, the resulting flash - generally followed by lots of swearing, makes me laugh... :-D
especially when there a borrowed pair