I think what he is referring to is the tab of the receptacle itself becomes the series element (which technically it does).
So let me expand on that. Is the tab on a receptacle rated the same as the receptacle? (ie-a 15 amp receptacle would only be capable of passing 15 amps through the tab downstream)
If so, is it legal to wire a 15 amp receptacle into a #12 awg 20 amp circuit in the "backstabbing" manner noted above?
