The 29-year-old helped his country to Grand Slam glory nine months ago, a decade after making his international bow as a wide-eyed teenager.
Ireland have provided the Magners League Champions in both the past two seasons, as well as on five out of eight occasions since the tournament was introduced in 2001/02.
And with three of the country's four provinces currently in the top five in the Magners League standings, things are certainly looking bright on the domestic scene as well as the European and international fronts.
D'Arcy, who starts for his country against Fiji at his home venue of the Royal Dublin Showground on Saturday evening, puts a lot of the most-recent success down to an increased competition for places among the provinces and the national team.
"I don't believe it has ever been this been this intense," D'Arcy told the Irish Examiner.
"This is probably the most competitive period, from Leinster right through to the international team.
"The so-called younger guys now have 15-20 caps, so they're not exactly novices any more. They might only be 21, 22 or 23 but they can't be called inexperienced. They've all played, they've all won a Grand Slam or achieved something big.
"It's just red-hot competition - which is the way the coaches want it."
That competition has seen his own international place come under threat, as well as that of fellow Leinster veteran Shane Horgan, but D'Arcy insists that he is delighted that competition for places continues to rise.
Injury saw D'Arcy lose his place in Ireland's starting XV to Paddy Wallace, with the Ulsterman still first-choice under Declan Kidney.
Horgan, a hero of so many Irish victories over recent years, had also become more of a squad man than a regular starter under Kidney but injury to Luke Fitzgerald has given the giant wing another chance to impress this weekend.
"It has to be a good thing to have competition everywhere," added D'Arcy.
"I don't need to go through Deccie's speech again about building a squad of 30 but that's what he's been doing.
"Competition is a great thing in a squad. You look at all the teams in the world that do well - they have a load of players with 20-25 caps; they have experience. With that type of competition, it basically means you can't afford to have a bad game.
"I didn't read any of those so called epitaphs written about Shane. From the tail-end of last season and the beginning of this, he has been a stand-out performer.
"You can drift off the radar but if you work hard you can get back in. Shane is the prime example of that."
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