RFC 2046 multipart/digest
A standardized method of sending a set of email messages as messages, rather than copied into body text, predates Microsoft Outlook.
A standardized method of sending a set of email messages as messages, rather than copied into body text, predates Microsoft Outlook.
MIME may be the technically superior solution...But like Betamax and MiniDiscs, it lost out to the easier-to-use solution.
A MIME digest would be used for the case that you want to provide someone a bunch of messages they don't already have. In that case, this brings up another reason this is superior to including the thing as text: it preserves all the threading and other metadata.