I don't think the difficulty or lack of relevance of license tests is the big problem for me.
You see, in GT3 and GT4 (and to a lesser extent GT1), I would go back to the licenses and try to polish my times. The effort and time put in to extract every last possible millisecond of time in the tests was worth it. The goal in GT4 was to go 2-3% faster than gold times at least, usually much more than that. Due to the diversity of tracks and cars I was driving to the absolute limit, this helped make me a very fast GT4 driver.
The problem is, I can't do that in GT5. For one, many tests aren't time trials but instead are races. But the biggest problem is the Skid Recovery Force that is turned on in the tests. The physics are completely different from the physics in the rest of the game. It won't be worth it to work on the tests like I did in the previous 4 GTs.
I agree with SagarisGTB.
Used to sit there completing all the licences before I raced. When I got bored of racing I would go back and try to get silver and then gold in them.
Not sure if I can disable Skid Recovery with the wheel I'm using.