will it stop those who really want to smoke? no... will it decrease the ammount who do smoke that are under 18, yes, definately... may be kind of hard to really beleive, but there are going to be alot of them out there who say 'fuck it, it's to much trouble now'.... is it a good idea? not nessicarily... unless they specify just tobacco (which i highly doubt) this will also include blunts, papers, pipes/bongs and everything like that... i'm not sure if 'kids' in england are allowed to buy this stuff now at age 16... but if they are... atleast as of now...i wouldn't be to suprised if come october you find out you can't anymore...