it would never get enforced properly. How do u know whats drunk, some people drink 12 beers and barely show any signs od drunkeness, while others may show it after one or two. This also creates more stress for owners and stuff, combined with the pressure of underage drinking, and many other laws the club needs to obey, it's crazy. Also the strength of certain drinks, this will seem to encourage people getting stronger drinks so they don't have to go to the bar as much, hmmm, not sure if thats what the gov. wants to encourage. So that means that as an average joe at a bar, when u decide to shout your mates, you need to determine wheather they are drunk, even if u have no training in the matter at all, and if your opinion defers from the publican..bad luck.
All and all i can't agree with this tactic, seriously, they should target other activites involving drinking, like drink driving and underage drinking rather than this issue.