Can someone clarify this code section. Does this mean that the white conductor in a 14/3 romex cannot be used for the return conductor to the light? I see this used all the time for the return conductor . Usually not re-identified and usually at the end of the line(single gang box with a 3-way switch installed) where the feed is on the opposite end and the light feed is in the same JB(in the middle of the run) as the 14/3 to the switch. If it can't be used can it be used as a traveler instead and re-identified to meet code?
I believe thst (2), together with other parts of this section, are only trying to make it clear that, whatever the situation, you have to re-identify the white wire when it is used as anything but a grounded conductor (neutral).
It also may be counterintuitive but you use and reidentify the white wire as the "hot" side of a switch loop. That way at the lamp end the installer is still presented with a black "hot" from the switch so wiring the light is W/W, B/B. Easy to keep straight years after that black tape would have fallen off from the heat of the light. Actually the reidentifying wasn' code unmtil recently although it was the right thing to do.
Your statement is intriguing to me. I have helped replace bad switches and the like (no-permit work), and even sans license knew enough to re-tag them (if I found them un-tagged). For me, it's common sense- "What you know the next guy might not."
Note how the code reads. It does _not_ require re-identification of the white conductor. Instead it _permits_ the white conductor in a cable assembly to be used as an ungrounded conductor in three possible uses. a) If it is re-identified. b) if it is the supply to a switch loop _and_ it is re-identified. c) If it is part of a flexible cord used to supply equipment. Note that in situation c) re-identification is _not_ required, and it is assumed that an electrician will understand how the conductors in the supply cord are being used.
In previous versions of the code, situation b) did not require re-identification, and it was assumed that an electrician would know how a switch loop operated and that re-identification was needless redundancy. It was clear that the electrician had the _option_ of re-identifying the conductors if they wished to use the white conductor as something other than the supply to the switch loop.