I get a lot of email. Read again, A LOT of email. I am subscribed to quite a few mailing lists for a bunch of open source projects and Linux distros. For the most part, I read and delete mail rather quickly. Sometimes too quickly. A few times after reading something in my non-mailing list mailboxes, I wish I wouldn’t have deleted so quickly. Thank goodness mutt is has so many configuration options.

folder-hook . 'macro index d '
folder-hook =INBOX$ 'macro index d "=INBOX.Trash"'
folder-hook =INBOX.Daubenspeck$ 'macro index d "=INBOX.Trash"'
That is all it takes. The first line is the default catch all. In my example, it tells d to act normally and delete files without the trash. The second and third line does the work for the two mailboxes that I need a trash folder for.