It started with Landon yesterday who kept capslock on main. Lots of people told him to stop using the caps but there are no real rulebreaking at that point unless it breaks another one.
http://i35.tinypic.com/317h9ig.jpg
As I often say, I'd prefer to let go a guilty than punish an innocent.
However, I suggested those people to go on the suggestion forum if they don't agree with the rules, just like I usually do when someone doesn't agree with what is in place. I generally explain to the player the logical reasons why a rule would be there, but there were no rule to defend.
As a moderator, I don't want a rule "ok you can post X and Y caps and so and so and so". This is too tight to apply.
If a rule has to be voted, it would be about "excessive use of caps" just like we have a rule for "excessive swearing". There would be a grey zone just as usual. Those rules are about what we judge to be
excessive. Keep this in mind : We each have our own tolerance level.
That said, I would probably vote against such a rule anyway.
Edit: Typos
Edit2: More details, added a screenshot.