The code itself isn't actually muddled, as it states green/white top and bottoms or "club colours". <<snip>>
To fix this, GNAS need to wipe out the current club colour register and insist that club colours revert to base green, black or white tops with either green, black or white bottoms. Alternatively they could scrap it, and then we'd have a spectrum of colours and styles of dress (including denim, ripped or otherwise) and a general look of a "have a go", rather than a serious tournament.
But since it does not state what the correct shade of green is without a swatch to compare it to or a licensed supplier of "official GNAS Green clothing" then the rule is open to all manner of argument and interpretation. Black and White on the otherhand do not suffer the same degree of uncertainty of shade but black is not allowed unless its your club colours....
I personally would not like to see the clothing rule scrapped but unless they can do something about the vaguery of green then black needs to be added as a base colour.
As to club colour checking it wouldn't be beyond the wit of man to include a page in the ROS with some pretty pictures of current registered club colours . If there are rules they should be applied without favour every time a comp is shot.
Good shooting.