So implied Descriptions. You can override them in the Doc Editor if you fill out the form. But basically if the Doc record is empty, show the UDT Description in lieu of the empty doc record Description field.
We already do something like that with I/O and Extra Info Doc field. If there is no Extra Info field for a specific I/O record (e.g. X, Y, WX, WY, RX, RY), we fill it an implicit Extra Info detail showing the module position, (see attached screen shot)