Lol. Shopping areas are the worst. Industry is usually more careful. I've had to chase power flukes with modern electric components clear to high tension lines. Being wye or delta made a difference even at the 120v knockdown. There is no way of knowing how things react until you try and designers rarely seem to have or even consider, wye AND delta access. After a day or so of strike outs, I checked to see what the engineer used (takes time and lots of calls)
There will always be trouble somewhere, sooner or later. You can usually change things to accommodate a workaround, finding where and why on a board is the challenge. Electromechanical is much more forgiving.
Strummer, I've rarely met a guitarist without some electrical experience... sooner or later those knobs, pickups, cords or effects don't cut it and things get opened. Sooner or later the info from both activities will meet, then "look out world...it aint Strummer it's "Strutter"" 
