Hughes said: "People laughed when we said many years ago that one day the club would comprise a vast majority of British players, and Londoners as well.
"But here we are. Look who's laughing now; we have two London kids who made their full bow for England in the World Cup squad after just five years in the game. That's just remarkable.
"How many more like Louie [McCarthy-Scarsbrook] and Tony [Clubb] are out there just waiting to come into our sport? And we've even got clubs in the north of England coming to London to recruit players we have developed. That's how far we've come."
Quins' success in developing their own talent saw the club rewarded with one of the three-year licenses to compete in the revamped 14-team Super League.
The new regulations have abolished relegation but McDermott is more concerned about the other end of the table and is convinced his players are capable of challenging pre-season favourites St Helens and Leeds Rhinos for top honours.
He said: "We're out to win the competition. We have more depth than ever before as a club and we have recruited well in key positions.
"Yes, there is far less reliance these days on imports but we owe a lot to those players who came to the club in years gone by and have helped in getting us to where we are today."
Clubb shares his coach's optimism and says the players are in confident mood ahead of Sunday's season-opener against Bradford Bulls at the Twickenham Stoop.
He added: "The play-offs is our minimum target. We've trained for seven or eight weeks and we look stronger and better than we did last season [when they finished ninth].
"We need a little bit more consistency, as well to be able to shut games out.
"There were a few times last year when we built up a good lead and then let it slip. We've got to stop that this year."
