Allen.cole, my uncle taught me to weld that way.

You said "it lasted a hundred years so it can't be all bad"... but that's exactly the problem. It's a hundred years old. The insulation gets brittle and cracks just from age, even if nobody touched it. That hidden crack is a fire waiting to happen. Saving money isn't worth betting your house won't burn down. People panic because the danger is real and invisible.

Actually, I've seen some welded ones hold up just fine!