Hey just because someone who has been playing for 12 years can't play it, doesn't mean that someone who has only been playing for 2 years can't either.
I think as piano players, we should all know that time is irrelivant, because it really depends on the player. I know people who have to go over something 500 times to learn it and other people who only need to look at it 3 or 4 times. If you're really dedicated then you should be okay =]
I've been playing for less than 2 years myself and I've already moved onto grade 5, I don't have a piano, I have a keyboard. All I have is 1 half an hour lesson a week and I don't even practice that much (mainly because keyboards irritate me, but thats all i've got, so I deal with it) oh and I'm 15.
All I'm saying is there are pianists who are good, because they practice A LOT, for many years or whatever, and then there are pianists who are good because they are in love with the music, music is like their whole life. (or maybe you can just be one of those people who picks things up quick.) I mean, we've all heard of or seen one of those child prodigy kids who get talent from literally nowhere in the blink of an eye. either way, the only thing time is relevant for is experience, and maybe a build up of repetoire, Otherwise, quit kidding yourselves thinking that 'you know from experince its impossible' because this person could be a hell of a lot better than you. =]
so good luck ^^