My electrician cousin said stop ripping out the old knob and tube, and now I get why
He told me at a cookout in Rochester last month that half my rewiring job was fine because the insulation was still rubber and not crumbly. Anyone here ever kept part of a system after a pro told you to, or did you just gut it all anyway?
My buddy had the same thing happen in an old farmhouse and his guy said to leave the runs that tested fine, just swap the outlets. Two years later no problems, so I'd say trust the cousin if he actually looked at it.