But he said it was a moment that should have happened at least 10 years ago and an entire generation of NSW-born AFL players had been lost to the game as a result.
"If you look at the quality of some of the players - Lenny Hayes, Mark McVeigh - there's enough quality players through the old system, let alone if you'd had this set up 10 years ago," he said on Tuesday.
"You'd have some real quality players about to enter the draft with Greater Western Sydney coming in.
"Obviously it's an enormous opportunity that's been lost, because there are kids who would have been playing AFL football if we had have started this 10, 15 years ago.
"But ... we can't worry about the kids that aren't playing. We've got to make sure that a lot of these kids do play in the next five to 10 years."
From Tuesday until Friday, about 600 boys aged from eight to 12 will attend tryouts at Lakeside Oval with a view to being chosen among the first intake of the Swans' academy.
The new system, under which the four AFL clubs in NSW and Queensland will run their own development programs, replaces the NSW scholarship system from 2011.
Swans CEO Andrew Ireland estimated the club's academy, based loosely on those run by elite European soccer clubs, would cost at least $1 million per season.
Boys as young as 12 will take part and once they reach draft age, their clubs will have first call on their services. If another club expresses interest in drafting an academy player, a bidding system similar to that used under the father-son rule will be used.
Roos said he hoped to assume a role with the club's academy on completing his coaching tenure at the end of 2010.
He also expressed his frustration at the AFL's reluctance to heed the Swans' calls for change in the NSW development system.
"Let's be totally honest - the only reason we've got an academy is because there's another team coming in Sydney," he said.
"We're going to need another 80 players going to Gold Coast and Western Sydney so we're going to have to get them from somewhere.
"We've wasted so much opportunity over the years, the AFL up here in Sydney. We've been here for 25 years and [in] the last three or four years, how many kids have been drafted out of Sydney?
"There's been a lot of wasted money and hopefully now we can turn some of that money into players which is going to help the competition as a whole."
Roos' sons, Dylan (15) and Tyler (14), will be among those trying out for the academy, as will the sons of key forward Daniel Bradshaw and former Swans stalwart Kevin Dyson.
Ireland, who has been one of the key architects of the academy system, said it would take several years before its advantages over the NSW scholarship program became apparent.
"While I'm sure there are a couple of scholarship boys who are going to come through and become AFL players, our view is if you look at that group of players ... that pool isn't quite good enough," he said.
"We're really talking about a quantum change, rather than just the individual talent that might sneak through."
And he rebuffed the notion that the Swans were interested in developing players for their own benefit at the expense of the game's greater good in NSW.
"Our TeamSWANS program does huge work in the general market - much more than any other club in Australia. That work is to help grow the game; this work is to try and develop kids to play AFL football and to play with us.
"We're not investing a million dollars a year into the program for any other reason, to be frank, than to produce AFL players and hopefully for us."