Earlier quoted context omitted.
An electrician in 1880 did a lot of design work. One of 1920 (and today) does it by rote - they just follow canned rules and procedures already worked out. It's all coded into regulations, too, so there's little flexibility. An electrical engineer, on the other hand, does design work.
>they just follow canned rules and procedures already worked out To a degree. I get the contrast you're drawing and don't really disagree. But an electrician (like plumbers/contractors/etc.), especially working in an older building, has to deal with a lot of unexpected circumstances that have to be dealt with. There's a lot of problem-solving involved.
So I told him I'd do the low voltage wiring myself. Those have to be separated from the A/C wires by a couple feet, and only cross them at 90 degree angles. No hum.
Inductive coupling is something a first year EE student would learn about.