ONE reason that a bonding conductor is mandated is the real world experience of looking at loose set-screw fittings.
I've seen rush jobs where it became obvious that the original installer was never returning back to tighten half of the set screws! He'd slap on a coupling, tighten it, slam the bare end into the running stub, strap it, and move on. Going back ten feet to hit the other setscrew was just too tedious for this fellow.
Needless to say: the bonding to ground was terrible.
This sloppy method is NOT at all rare. You'll see a lot of it on non-union, rush-paced work. (Big box retail, grocery stores, etc.)
I just witnessed a code violating EMT job at the local auto parts house. The EC didn't EVER strap EMT running from purlin to purlin when they ran square to the purlins. Instead, they just settled for a naked, unsupported run from box to box -- all in plain view -- this was an open ceiling scheme.
In similar situations, my EC would always use back to back nineties so that the EMT could be strapped to the purlins before being sent over to the other side.
As installed, the EMT is going to separate in any earthquake -- and this is California.
The EC did do a bang-up job straping LV flex runs to the F/A system, though. So he has that going for him.
