I disagree about PMing a mod. I PMed a mod recently to ask why a thread was locked. The mod politely explained why, and the reason made sense to me. It seemed almost obvious, actually, though I didn't have the faintest clue why the thread was locked before I asked the mod.
In my experience if you ask politely, the mods are very receptive. I appreciate the fact that this mod took the time to reply to one of who knows how many PMs from one of a thousand Ehellions.
Having the reason written down really helps me understand and learn not to repeat a mistake. I learned quite a bit from my PMs with the moderator. I feel that a short explanation would be very informative and useful. (Some mods already do this, and I really appreciate that.)
Ehelldame mentioned upthread that sometimes the reason a thread is locked is none of our beeswax. I respect that. In that case, it makes sense not to post a reason. But in instances where a thread is locked due to people being impolite to each other, thread going off topic, not enough etiquette in the discussion (for non-Coffee Break threads), legal or medical advice or venting, then I think it would be helpful to say why.
I think it would save the mods time in the end for two reasons. Indirectly, because people will learn from these notes and will be less likely to make the same mistake. Directly because someone who has once had a thread locked with a note at the end that says "Locked due to venting" will be very thoughtful before posting a thread that could be venting. The mistake will be less likely to happen from the same person due to positive, passive peer pressure. (Did not actually alliterate on purpose, but I like it.
What do you guys think?