Well Sidwell, Bothroyd, Muamba, Harper never made it at the club so I don't see how they are successes (they could only really be deemed successes if they make it with us or are considered good enough to play for us at the end of the day).
Theo was bought in reality, another club developed him and we paid big money to sign him.
Bendtner hasn't made it judging from his displays and people's views on him. For me though a true youth product is one that comes through the ranks, because AW's 10 year policy surely can't include players we effectively snatch from other clubs when they are 17/18 and thus have already learnt a lot from their home clubs.
Gibbs is a true youth who's come through the ranks, he's still to prove good enough though thus far, not convinced he's the real deal as a full back, as a winger maybe.
Cesc you could argue came through.
The 10 year plan represents home grown players who have come through the ranks from a young age though IMO, not players we signed from other clubs in their late teens.