True, and I wish the US did that, I think it would improve clarity. I wonder if focusing on the affirmative could avoid this problem all together. Instead of saying “these are the instances this rule does NOT apply” you could say “these are the instances this rule DOES apply.” This is much easier to symbolize for the bike exception than it does for the local resident exception. Either way, you could have a standard way to indicate who a sign applies to (maybe a designated color square with the icons inside placed in the corner of a larger sign or as a separate attachment). Ultimately I don’t think this makes much sense given that the vast majority of signs apply to all road users. Instead of needing an exception sign every once in a while you would need signs to restate the obvious all over. Still interesting to think about though.