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A succinct email in just a subject line
I’d never heard of an end-of-message signifier in an email subject.
This is highly appreciated by people who receive a large volume of mail, since it lets them do a quick triage on your message without needing to conduct a full examination. Maybe it’d work for internal email where you’ve established the protocol, otherwise I suspect you’d just confuse people. Incidently, Wikipedia has an article about End of Message, but all the references are the same vintage as that 43 Folders post.
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