I think a lot of Europe seems to do a bi-annual check.
I guess the question is do you then make the MOT test itself much stricter?
A lot of things that might fail, are often down to the testers opinion anyway, so a balljoint that has a tiny bit of play now, he might thing "it'll last a year" and pass it, whereas if it was two years would fail it instead.
The real issue is that people are basically too stupid to actually look after their car themselves. IMO a car should never fail an MOT. If it does, your not looking after it properly. I've never yet had a car fail a test, and although every time there may be one or two things i'm not happy with on the car, they're never bad enough to actually fail.