We usually enter detailed descriptions directly in Trello. When we hit "update Trello" in aha for the release, the descriptions in Trello are being deleted. We often resend the Aha Release to Trello to update the Due Dates, however, we don't want to delete any Trello card descriptions that may have been added directly in Trello.
We just released an enhanced Aha! integration with Trello that allows you to have full control over the way information flows between Aha! and Trello — in both directions. Plus custom fields, faster imports, and automatic updates.