I suppose Michael Witt comes into consideration. He comes through the grades at Parramatta, goes off in his first half year, can barely get a gig the next year, then he finds himself on the outer, goes to Manly, goes alright there and then I think he got injured/suspended and found himself on the outer, got a crack at the Warriors, starts off well, great goal kicker but never really dominated. Given the wrap on him coming through the systems and his start at Parramatta, its kinda bewildering. He seemed to have a massive taste of 2nd, 3rd, 4th, 5th, and 6th year syndrome. IMHO his biggest mistake is that he wanked on about being a five eighth, when he was a halfback. He played about 3 games for the Warriors at #7 and they were up there with his best first grade performances but then whinged his way back out to 6. Playing 7 allowed him to step the bigger forwards better, but he would not budge.
I don't think its coincidental that he was basically discarded by Parramatta, Manly and the Warriors. The movements there are all very similar. Starts off well, then really does nothing, and gets found out for not following through on the hype he started out with. He would have to go down as one of the most unfilfulled halves of the last 5 years, I know he played a lot of first grade but when he started at Parramatta he was amazing, 1000000 times better than what he followed up with.