Blokes like Matai, El Masri, and the Hughes boys would have come through Matthews, Flegg, and SG Ball, then into U20s (I forget at which point one the junior rep comps actually became the U20s), Premier League, and finally NRL. The likes of Mason, Price, Smith, and Anasta never played in the Dogs junior system at all. They were very much developed elsewhere, and purchased as a finished product. That was the distinction I was making.
I've seen Roosters fans make the argument that where a player makes their first grade debut is what matters. I cannot agree, for the fact that it allows teams to claim credit for developing players they simply poached from another team's Toyota Cup squad. BJ Leilua and Kane Linnett both debuted for the Roosters, but they had absolutely nothing to do with the development of either player. Similarly, although it is highly likely Josh Drinkwater will debut for us at some point this year, we can't claim any credit whatsoever for developing him. He is clearly a Manly junior in every sense. A few games for the Cutters while Price realises how shit Fien is doesn't change that.