Does your supply house stock #8 in white ?
Yes violation but bet most here have done it.
Never understood why it is fine on #4 but not smaller. Any good reason for this ?
Real question here is why installer did not simply run 2 ungrounded #10 and a white.
I've done the same thing too.
I too don't understand why it's not OK to mark any grounded conductor with tape, not just 4 and larger.
Why is it OK for conductors in cables and not for individual conductors in pipe?
Don't know, but it has caused a few problems for me too.
steve