The Saints were leading the final by 16 points at the break before a second-half rally saw Leinster secure a memorable 33-22 victory.
Northampton return to Heineken Cup action on Saturday - and they could not have been handed a tougher start in Pool One, with a trip to Limerick to face two-time champions Munster.
England hooker Hartley knows, though, what is required if Northampton are to go one step further and reclaim a trophy they last held 11 years ago.
"We had a great run to the final last year, but you have to play for 80 minutes and we did not do that," said Hartley.
"Obviously, it hurts, but it does not get any bigger than that in terms of big-match experience. We will learn from it.
"In terms of intensity - as it was in the final last year, as well as the quarter-finals and semi-finals - those games are as close to internationals as you can get.
"Munster have also been to Heineken Cup finals and won some and lost some. As a group they have been through those same disappointments, while also being together for a long time.
"As a squad we are still quite young with our best years ahead of us. We have not lost anyone, and we have added to the squad.
"That gives us more depth, which we needed, as we were playing pretty much the same team every week."
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