It doesn't really matter. If you are not recognizable, it's not valid. That is the whole point of a photo-ID the photo has to be a good likeness with you. Glad the GP met friendly people that let him get away with it but don't count on it working for ever :-)
The driver's license is not an ID, though. Besides, at least in Germany you get it and then it never changes. So the photo is pretty much always outdated.
My European driver's license expires in 2046, but the fine print says if my appearance substantially changes, or the police requires it, I must get a new one.