And the whole NEMA 10/NEMA14 thing...
It's a can of worms, but it was a can of worms long before 1999 (actually '96 IIRC). You can't explain the proper way to ground a range or dryer to a DIYer (something that really ought to be dirt simple), because every manufacturer has a different way of making the jumper.
Suppose you remove the bonding jumper and install a four-wire cord. Then the customer moves to an older house, and installs a three-wire cord, but fails to restore the jumper.
Or, suppose the customer buys a Bosch or other European-made dryer, which has no 120V components and therefore requires no neutral. What it does have is a floating neutral terminal that serves only to park the unused conductor, and a NEMA 6-15R on the back for plugging in a 240V washer. There is no jumper from the "neutral" terminal to ground. This particular oddity was not covered in the appliance installer's five-minute training session, so the appliance had no equipment ground, and would still not have one if an electrician had not been called in to relocate the receptacle (since it was a long circuit, wired with 10/2 NM, never code-compliant but long accepted here, I couldn't justify a NEMA 14 upgrade to the customer).
That's not to say that I think the '96 change was a bad idea. The confusion is traceable to 1947, when the practice of grounding an appliance through the neutral became officially sanctioned. The 1940 NEC allowed it only with special permission of the AHJ. Apparently, many inspectors allowed it due to wartime shortage of copper, and it was later formalized.
I personally blame this anomaly for the common practice of blurring the lines between neutral and EGC in subpanels. I wish it were only DIYers who were doing this stuff, but I've seen numerous examples where the offender was clearly an electrician. My codebook collection goes back to 1940, and I can't find where it has ever been legal to ground a subpanel with a neutral.
I received an email today from the Texas licensing authority. Today's news is that appliance installation now requires a license. I'm certain that the NEMA 10/NEMA 14 confusion is responsible for this.
The permitted practice of grounding certain appliances through the neutral was long justified on the basis of the excellent safety record of these appliances, but IMHO this missed the point. For simplicity's sake, we need one rule for services, and another for branch circuits and utilization equipment. I look forward to the day when NEMA 10 is a rare curiosity to be written up on an Electrical Nostalgia thread, but I doubt I'll live to see it.
If you make permits and inspections too complicated, people will DIY without them. If you make the code too complicated, sometimes even the pros will mess it up. And some people will DIY no matter what you do, so doesn't it make sense to make things simple enough that people can understand them?
</rant>
