We have an informational feed that gets sent out to subscribers.  What we would like is to create an email body in the website editor, then have the API inject information content into a paragraph in the body and send that out to contact lists.   It seems that most of the double-bracket substitutions are contact-oriented, and for short words & phrases.  What is the best way to substitute campaign-oriented multiline content into an email when a campaign gets sent out, all via the API? ... View more