Had a short slip in Copenhagen whilst in the bar having a post flight beer - a pax waited with one eye on his watch - just under 12 hrs before our scheduled departure time he walked over and told us that we were breaking the law!
We said we were governed by our countries law - which of course we weren't- and got away with it.
Didn't do it again.
Remember most crews would ignore the Indian 24 hour regulation - probably didn't know any better.
Personally I think the obligatory breath test is a good idea - especially after the ANC crash.