Just look in the front of the code book to atritecal 90.5 Mandatory rules. Mandatory rules of this code are those that identify actions that are specifically required or prohibited and are characterised by the use of the terms shall or shall not.
I think if you look at means of identifying grounded conductor you will see the word "shall" used a lot. It's a "Mandatory" rule.
People can sue you for anything but being stupid shouldn't be one of them.
I agree. I am sort of mixing personal opinions on what I think code should require and what it actually does say - and the topic of code becoming a design manual for the untrained even though it specifically states it is not a design manual comes up a lot. I guess I need to clearly keep comments on what is in there more separate from what should be in there.
One does have to draw the line on what to put in the code - true most qualified will recognize which conductor is the neutral - even in some cases where all are same color, but we probably still do need the general rule of white or gray to identify it. Which comes back around to the OP topic of why do manufacturers make this conductor in question yellow when they know it will be used as a neutral most of the time?
I think the real answer is this series of cable was originally intended for utility companies who do not necessarily have a requirement to identify it with white. Is also possible the yellow is easier/lest cost to make then white, or maybe is better sunlight resistant or something. Understandable for the original URD that was not rated for inside use, but then they started making dual/triple rated stuff that is suitable for inside use and still continue to mark one conductor with yellow:roll: