We are talking about a Direct connection of a screw to Equipment grounding conductor with box clamp screws, As far as a LUG to an equipment grounding conductor common sense says a Good connection made by a 1/4 20 ect done right well be code compliant. This started off as a simple question then guys started adding lugs ect Question Was an Equipment ground wire being hooked to a cable box clamp Screw , not a metal box , not a ground bar ect. Its not only a matter of the code to me but proper workmenship .Otherwise just grab any screw in any box hook the gr. wire to it!!I say again the Head on a box clamp screw to to small , Believe me been in the trade a long time i tried it.
