I saw this on a mailing list recently, and it bothered the fuck out of me. Edited to, well, not detract from my damned point to be quite honest:
>>> Original poster wrote:
>>> A question for you more experienced people: [Question that was recently discussed]
>> Reply wrote:
>> Didn’t we just have this conversation recently? [A curt summation of some points]
> Useless Reply wrote:
> Yes. Yes, we did. [End of message]
Way to be a cockbite to the poster, guys.
Yes, you had that conversation recently. Did the original poster? Maybe they just joined the mailing list/forum/whatever. Maybe their lives were busy enough to where they didn’t notice the thread before. I sure as hell didn’t–as far as I’m concerned, that was the first time in a bit this conversation happened. Or, and this might be a shock to you all, sometimes people ask questions in different ways because their brains are wired differently.
Your experiences in a community are not universal.
Your context in a community is not universal.
Your history, both distant and recent, is not universal.
Your brain’s wiring & information processing is very much not universal.
Stop acting like it is. Stop shaming people for not sharing your brain. Stop being cockbites.
Here’s how the reply should have happened:
>> Original poster wrote:
>> A question for you more experienced people: [Question that was recently discussed]
> Reply wrote:
> Hey! We recently tackled this. You should check out the discussion here [link], but in short here’s the answer: [answer]
It’s interactions like these that turn people off of communities and hobbies. I almost said “it’s people like these…” but that’s unfair–nice people have off-days, and I don’t have the experiences, context, history or brain wiring that those people have to know if this is something they regularly do.
Oh, and if your reply is to just dog-pile on someone, like Useless Reply did above, just walk away. You Don’t Need That Third Taco.
Still, bad interaction. Bad form. I feel bad for the original poster because it was just an innocent question from someone who lacked mastery of a topic that could have been treated with a little more respect. After all, each and every one of us started out lacking mastery of the things we love today.
A final point: politeness in replies is like putting a little english on the shot that’s your point–it helps you get the point across.
 Maybe not the best metaphor, but I do like the phrase “put a little english on it.”