I have the same requirement in which users cannot be allowed to see others' data, even in thumbnail form.
Even worse, all my users will have permission to see a non-empty subset of the data, which means I cannot even force the "User Specific View" blank thumbnail to display by selecting a user that cannot see any data.
Getting back to Robin's example, it seems appropriate to have two additional options:
- For each of the four users, generate a unique thumbnail using their user filter.
- Don't create a thumbnail (as Robin suggested).
What I will suggest is ...
.... to create a separate user-account for Deployment(Publish) only but do not grant any other permissions.
because this account cannot see any data.
Of course, you must implement the Data Source Filter to secure your data based on the login's username.