During a recent upgrade of Cognos 8.4.1 to Cognos 10.2.0 one of my developers noticed that he no longer had access to create
Drill-through Definitions. The item in the menu was gone yet administrators still had access to it. I did a quick test and added him to the "
Drill Through Assistant" capability with full permissions. After a log out and log in he had the
Drill-through Definitions menu item again. So I started to do some digging. Turns out the functionality was changed but was never added to any of the Cognos 10 documentation up to and including 10.2.1.1.