Quoting Michael Paoli (Michael.Paoli@cal.berkeley.edu):
You've emailed/posted/etc. many many times about how to, and how not to post to lists, etc. (e.g. plain text, don't do attachments, etc.) ... and we thank you very much for that! :-) ...
To hopefully be a bit more proactive, do you have recommended web page(s) (most any suitable URL will do - but probably best if it's a web page or the like that at least somebody somewhere can tweak/update as/when suitable, rather than a read-only archived message that's web accessible) somewhere on that topic (if not, we could potentially create one, if we wanted).
Let me take another swing at this one, and my apologies for having been rushed. (I'll still be rushed, but have some thoughts I'd like to articulate, from a slightly different angle.)
There are indeed pages out there that give tips about how to best participate on mailing lists as to posting style, things to do and not do, etc., especially as a newcomer to the online technical community. I can hunt them down and cite them -- but so can you. ;->
The thing is, most of the time those don't work very well, and, if you think about it from the viewpoint of _process_ (sequence of events), the reasons for this (general) failure become evident -- especially when one's primary aim is to reduce the incidence of misbehaviour. One is that someone about to post essentially never stops to think "Oh, maybe I should stop before posting and go read this group's tips on how to participate first, so I don't mess up."
There's a necessary distinction between lists of tips and lists of allegedly enforced mailing list rules -- but neither of them tends to work well (in the above-described sense). The people who would most benefit from them, i.e., those who genuinely don't know how to post cluefully and why, are least likely to read them (especially in advance).
And then there are those who _do_ know better: These will often ignore any posted rules or guidelines entirely, and if challenged will cite nonsensical, invented-after-the-fact reasons why they're supposedly an exception -- or a corner case that they'll assert that you haven't covered. (Computerists tend to madly adore babbling about alleged corner cases.) A large fraction of computer geeks think that if something is posted somewhere, and expresses a point of view, that implies that the matter's up for debate. The more you write on the subject, and the greater the detail you expound, the more they assume it really is up for debate.
You couldn't possibly be serious, they think, if you're that verbose. They're trained to think that a big, red sign saying only "STOP" is probably serious, while one saying "Stop, except of course as required for safety, e.g., to get out of the way to avoid collision, and in certain other cases" isn't serious at all. That's human nature. That's how _real_ people think, which is just not the way computerists assume they do.
Moreover, most people in all populations operate from a tacit assumption that, if it's physically possible to do something, it must be OK -- that any rule worth respecting is enforced in a way that makes it the path of least resistance, and that any rule that can be ignored is just noise. Suggest to them that they should _not_ follow the path of least resistence just to do the right thing, and they'll want to know why they should do you a favour.(!)
(Consider the number of technical people on Linux mailing lists who post from GMail and who both top-post and quote entire prior message threads in every posting. Do you think it's because they don't know that's wrong and rude? No, they're almost uniformly fully aware of that. They just can't be bothered to do anything requiring extra effort.)
And then, a certain number of people will argue with anything: If you put up a page saying "Please don't post Lotus 1-2-3 spreadsheets", someone will figure out how to create one, and post it, just to push back. Or invent some alleged corner case, and do likewise.
A great many cultural-norm rules are present in automatically enforced form, by being embedded into the software. In many cases, those magically cease to be perceived as rules: They become perceived as merely the base reality to which subscribers accomodate themselves.
For example, Mailman has a built-in ceiling on individual message size, which by default is low enough that it snags almost all, e.g., MS-Word attachments, but high enough that all legitimate postings go through. Do we see a lot of angry postings protesting the listadmin's tyranny in cruelly rejecting Joe User's 40MB PowerPoint attachment? Nope. Joe gets the automatic reject notice, and thinks "Oh, I guess I can't do that." No debate then ever arises.
Back in Majordomo days, there was an incessant tussle with people who erroneously sent "Please unsubscribe me" postings to the broadcast addresses of mailing lists. They would screw up, get chewed out for being twits, protest the supposed purity of their motives as making it perfectly OK to be asshats in public, attempt to blackmail their way into having the listadmin figuratively wipe their noses for them (i.e., unsubscribe them anyway just to shut them up), and so on. Mailman put an end to about 99% of that through its automatic "administrivia" filter that intercepts most such posts and redirects them to the listadmin.
The crossposting is another case in point: People here may recall how I kept politely asking Kristian Erik Hermansen and several other people to please cease crossposting between svlug@lists.svlug.org and sf-lug@linuxmafia.com -- and his reaction was to scream listadmin oppression and keep doing it, keeping his roster of recipients down to a few, to avoid the "Too many recipients" filter. (People who responded to his posts, in contrast, often hit that filter, because they added one or two recipients in replying.)
I tried for many months to just ask people nicely, and the problem kept getting worse, and eventually just created a couple of filters to intercept and autoreject a couple of the most common crossposts between svlug@lists.svlug.org and elsewhere. And, immediately, no protest marches or namecalling about the mean listadmin, and no more attempts to crosspost after just one that got bounced: That's because it was now seen as built into the software, instead of being something in words, which is then seen as the user being asked to do someone a favour.
Now, I am _not_ suggesting hiding into the software various attempts to manipulate members of mailing lists. A smart listadmin seeks to cut to the absolutely bare minimum the amount of hassle that he/she and also list subscribers need to endure. A smart listadmin runs the mailing lists' unmoderated to the extent possible, and tries to automate everything that can be processed without his/her help. Less regimentation and control means less work, less friction, more pleasantness.