Issues updating a keyboard shortcut that is mapped to multiple behaviors

In the keyboard shortcut editor, if I try to update a keyboard shortcut that has been applied to multiple behaviors, both behaviors get obliterated and only the one new behavior assigned to it remains. 

For instance, I wanted command option c to map to copy with relative property links instead of the default. That shortcut is also mapped to remember interpolation for footage item. I don't like the default for copying in the timeline, but I do like the default for copying interpolation in the project window. If I want to update the timeline behavior, I lose the project behavior.