The 2008 Magners League winners are currently without first-choice fly-half Jonathan Sexton but Gaffney has been hugely impressed with the performances of his replacement, Shaun Berne, as well as those of new scrum-half Eoin Reddan.
With Sexton currently out injured following his memorable performance for Ireland against South Africa in November, the experienced Berne has become a central figure in Leinster's search for domestic and European success.
And former Saracens, Munster and New South Wales Waratahs boss Gaffney, who knows Berne from their days in Australia, has been delighted with the manner in which his countryman has stepped up to the mark, particularly as he has hasn't played regular rugby at fly-half since swapping hemispheres.
"Shaun is a very smart rugby player," said Gaffney, after the 30-year-old produced a commanding display in the Heineken Cup win over the Scarlets.
"He has been maligned over time that he can't do this, or he can't do that. But knowing Shaun and going back a long, long time with him - probably 10 or more years - I know how skilful a player he is.
"Shaunie hasn't played a lot at 10 for a number of years. He wasn't the first picked 10 at Bath, though he played a lot there with New South Wales. With the Waratahs he played more at 12.
"I think he showed that at the weekend, not just with the fact that he's able to run the ball, but some of those glimpses where he knocked the ball down the right touchline, down the left touchline and back over the wingers heads, some smart play. And I think we needed that at that point in time. We needed to be able to mix our game up at that time."
As for Berne's halfback partner Reddan, Gaffney has been delighted with the way in which the summer signing has adapted to his new environment.
The ex-Connacht and Munster No9 returned to Magners League rugby after a four-year spell in England and has immediately become first-choice at his new province.
Reddan, who has 17 Ireland caps to his name, has appeared in five Magners League games so far this season and is likely to continue to play a big role in Leinster's attempt to retain the Heineken Cup and secure a Magners League play-off berth.
"Redser (Reddan) did play very well the other day," added Gaffney.
"He has been working very hard at certain aspects of his game because we're playing a lot differently than how he would have done with Wasps over the last number of years.
"When Redser left Ireland I thought that he was technically the best passing nine in the country... and the service that he is giving at the moment was instrumental in us getting that performance against the Scarlets."
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