I don't really care about it, but I think 2 plates are still better:
Here in AUT, we always had to put up 2 plates on cars, but when passing a radar box it was only allowed that the radar box flashes the rear plate, because of security concerns (the flash might blind you and cause an accident).
That was changed in 2010, because German tourists who speeded in Austria and passed a radar box could not be fined.
Why ?
Because under Austrian law, the holder of the car gets punished no matter who drives the car, while under German law only the driver gets punished, no matter who's the holder.
So, the Austrian authorities had always a problem: If a German driver got flashed from the rear, only the back license plate was visible, but not the driver's face. Which led to many cases where the German touris said for example "their wife was driving" and the driver was not fined.
Starting in 2010, Austrian radars were then upgraded to flash the back and the front plates in a way that the driver was not blinded but also in a way where the drivers face was clearly visible. At the same time, the EU introduced a law which mandated that EU authorities in every country can fine traffic offenders from every other country. So, no excuses anymore for the German speeding tourists. They now get a clear picture with their faces on it sent to them by the Austrian authorities with a hefty fine next to it ...
Also: Austrian police officers using radar-thingies will usually always measure your speed from the front plate when you pass them.