https://smbx.org/bsg-guide-for-sending-email/
Proposed Symbolics guidelines for mail messages
BSG 4/11/84
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It is customary to attack the someone by including his or her message, indented (unless you are using MM), and replying point by point, as someone debating someone they are watching on TV, or hearing on the radio.
It is considered artful to append many messages on a subject, leaving only the most inflammatory lines from each, and reply to all in one swift blow. The choice of lines to support your argument can make or break your case.
Replying to one's own message is a rarely-exposed technique for switching positions once you have thought about something only after sending mail.
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You get 3 opportunities to advertise your Rock band, no more.
Idiosyncratic indentations, double-spacing, capitalization, etc., while stamps of individuality, leave one an easy target for parody.
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