You obviously know what you are talking about and I would like to add......
I remember when I bought a new car for my wife from the dealership here, they asked her if I wanted the fake red license plate or the real one.
From what I gather the real ones (red plates) have a government stamp on them about the size of a ten baht coin on the bottom right of the plate, fake ones don't have it. Thing is though, that usually now the dealerships say deposit 3k with them and have a real red plate and get 2.5k back on the issuing of the final plate for the car (sales staff scam), or take a fake red plate for nothing and take your chances with the cops on the road.
I think that every dealership has paid for X number of real red plates and offers the choice to the buyers but I think the real red plates belong to the garage. Just a thought, but not sure 100%, more of a guess.
Don't forget....you can't drive your new car at night or even your second hand car if it has a red license plate. That's another one I'm still trying to figure out.
I think you can now but the brown log book stipulates that you need a police officer's signature in the log book to authorise you being in a different province at night and the officer's signature has to be from the province you are currently in.....so requires you to report to a police station to get said signature in the first place. I agree, it is a completely strange way of doing it with new cars. Having said that though, it's nothing 500 baht wouldn't get you out of if you got stopped at a check point.
So, in other words or layman's terms, you are still probably right as most will not go to those lengths to be able to do it. A red plate is a magnet for the cops and extortion money on the highway.
I remember when I got my driver's license....I had to take this exam on a computer at the DMV........
That must have been a while ago BF, as now in Joho, they issue licenses without taking the test if you have an in-date license from your home country and only require you to provide the med certificate and do the reaction test and the depth perception/peripheral vision tests etc before giving you a license. If your license from your home country is out-of-date then they still make you do the written exam, which as you say BF, is a joke with bazaar questions left, right and center.
The one I'll never understand here BF, is that you can buy a car without a license, drive it home and then learn to drive with it.
:waiIt was sold all ready. Thank you for all reader. 
