Job Auto-leveling: Yes or No?

[Razor]

If you spend a year and a half learning karate, and there are 5 karate skills you do not know, you do not spend another year in a class that teaches something you already know. You get someone to specifically teach you those certain skills you have not learned, and then you master them on your own.

That is assuming that a Job is simply going to have just two or three extra skills. By narrowing your class action choices I understood it to be that Jobs will have their own array of abilities and allow only a slim number of other actions to be set. But since we're both operating under assumptions, either one of us could be entirely wrong.