I have a requirement to disable some functions from a responsibilities for certain users. I have the option to create 2 responsibilities and exclude/include the desired functions, but the problem with this approach is I may have some cases where i will be obliged to omit just a single function for the user and on the other hand a certain user may required to exclude another single function. If I follow this approach I will have huge responsibilities and this will be hard to control.
Your understanding as per functions,sub-menu,menu,responsibilities and menu/function exclusion is correct. But I believe that is how Oracle works and you will have to list all the menus and functions in the responsibilities and then assign it to user and as far as I know there are no workaround brother.