I have never heard of anything more than a plug/cord connection as being the required means for disconnecting any appliance. I can see the value in having a breaker handle lock on a hardwired oven or cook top (though I still disagree). There comes a point in time where the NEC cannot protect the stupid from their own stupidity.
In a typical home, if the husband (or wife) is making a repair to a cook top, wouldn't it be safe to assume that everyone in the house is probably aware? How much of a risk is there that the husband gets electrocuted because the wife haphazardly goes and turns on the breaker? (Well, in my house, I could see that happening intentionally but that is another subject).
While I'm having an Andy Rooney moment, how come shared neutral/grounds, hard-wired ranges and dryers, along with no disconnects have been perfectly acceptable for decades, then ten years ago they suddenly became dangerous?
The range in my house is now on a 4-wire circuit, but only because it is connected to a generator sub-panel. It was originally on a 6/3 AL SEU cable. My dryer is still on 8/3 AL SEU since the house was built in 1992. Me thinks that someone out there is getting a bit too carried away with
potential risks. Are there really any documented cases of injury or death being caused by the lack of these recent requirements that exceed those of other electrical injuries? Nope.
I know, I know......Lead paint, driving without seat belts, smoking, riding bikes without helmets, asbestos, etc. weren't discovered until the damage was done, but come on.
Sounds like manufacturers of 4-wire cords, receptacles, disconnects and handle locks are constantly busy at work in changing the code (A.K.A: Reinventing the wheel).
Personally, I feel that the 4-wire requirement is actually making things more dangerous, since DIY's and appliance delivery boys aren't making sure to keep the neutral and ground separate. In my travels, I often find (even in new homes) that the bonding strap has been left in-place or removed in the incorrect scenarios.