Originally Posted by
CPH-Flyer
I think you are missing a subtlety. If you are here on a longer term visa or residence permit and exit/enter the country the stamps you get are different from the stamps you get when you enter the first time. It will be clear from the stamp that it is not your entry, but a return to Japan as part of a longer stay. So if anyone actually looks for/at the stamps, they will know they are not the relevant ones for this purpose of being allowed to use an international DL.
I am aware of all of that. "if anyone actually looks" is the operative point here. Someone else in this thread seems to imply that they don't always do so. It's also quite possible that not everyone working the counter at a car rental agency is aware of the subtlety you mention. I'm not promoting that anyone do this, nor am I even bringing it to anyone's attention, nor do I think it's a good idea. I'm just commenting on what someone else already said in this thread, and that seems to be rubbing some people the wrong way.
My worry here would not so much be whether the rental car company notices or not. But if there is an accident, it would pretty quickly be obvious that the driver did not have a valid DL. Then good luck with the Japanese police and the insurance companies.
That would be my worry as well.