I've filled dumpsters with K&T in my carear.
I suppose at one time it was a premium install, after all much of the world continues to operate on this fairly outdated wiring method
If in fact it was left alone it is usually not the worse for wear, it's when the years of retrofit, tag-on, and similar intervention starts that bad things happen.
20 years ago, a home inspector in his 70's whom had previously been an EC installing K&T told me 'you young bucks are'nt going to top this method'
maybe he had a point? we've been trying to one-up the mighty fuse ever since also.....
