Personal Content and Flaming
Amidst all the vivid discussion on the lang-dang list, one day by pure chance Armano found out Marina and he were somehow related. Not only was it amidst the discussion, that discovery happened while he wrote a message to the list.
Of course he wanted to tell Marina the news right away and began typing at once. But then he thought: "while it's interesting for us to have common ancestors, how interested will the others be?" and created a new message addressed to Marina alone instead of the list.
Private messages to individual members of a mailing list do not belong on a public list. Neither are others interested in your personal conversation nor are you interested making your private conversation public; the exceptions to these rules certainly confirm them. Compare that to using a cell phone on a train, for example: although somehow this has become a convention (to be accepted), for me it is a annoyance. With email, you do have an easily available private channel for communication.
It is a bit difficult (albeit necessary) to define what flaming is. The essence of a mailing list is discussion. Discussion can spark disagreement. When such disagreement results in messages leave the track of orderly discussion and become abusive, irrational, derogatory or personal they are flame mail. Thus complaints about new list members asking old questions can also be flames.
Fortunately, you will know a flame when you see it done -- by others. The goal is to detect one's own inappropriate messages as sharply. Then the options are either not to send anything at all (usually a wise choice) or to rephrase.
If you must flame, do it personally. While not all personal mail is flame mail all flame mail is personal mail. (Yes, you can flame "the list". Then it's... "personal" to the list (represented by its members).)
Whenever somebody starts flaming on the list nevertheless, the best thing you can possibly do is: nothing. Keep cool and those fighting will cool down as well (they'll get bored). If it seems appropriate, you can remind the involved parties (or the sole offender) how to behave online in a private message.