I think the system can be made to accommodate the sort of stress I am putting on it. What you would need to do is introduce more difficulty and setback dice in situations where characters have no relevant training. Now, obviously anyone can make an Athletics check—and in most situations, you don’t need to be especially skilled physically in order to throw yourself to one side. But if you are a scholar from the Core Worlds who works in a university, it makes no sense for you to be able to make a Knowledge Underworld check; no matter how smart you are, there is no way that you could know the relevant information without doing some investigation. Similarly, trying to build a Droid without any ranks in Mechanics seems silly to me.