I think you are right. This fine configuration isn't possible.  On the other side we use the basic role of reviewer with an approval flow to validate a task by team member that don't need full access. They are able to leave a comment, upload a document and approve (or reject) the task. 

It's a serious limitation for a marketing platform... not being able to delegate documents....

Hi ! Thanks Doug for potential workaround. Unfortunately that will not work on my side. Really hope that this will be improved on workfront at one point. Submitted a related idea : https://one.workfront.com/s/idea/0874X000000oOaaQAE/detail Cheers,