The day after Dublin's 17-point demolition of Monaghan in the All-Ireland quarter-final I was down in Waterford, and was ear-wigging on a conversation about their minor hurlers who were beaten by Kilkenny in their All-Ireland semi-final.
Surprisingly the conversation shifted to the Dublin footballers and their performance the night before with one guy saying that although they were playing well, the worry would be that they hadn't been tested which could stand against them when they met Donegal in the semi-final.
The response, however, is what stuck with me, particularly in light of last weekend's semi-final where for 35 minutes Mayo laboured under the weight of trying to restrict Kerry, rather than imposing their own game-plan.
As the older party to the conversation said: "Dublin should let Donegal do the worrying".
While modern day football isn't quiet as simple as focusing purely on your own game, the significance of the statement should resonate with Jim Gavin. Although he designates key defensive duties to individuals, he has in his two years at the helm always set his team out to play to their strengths, which is effectively man-on-man, open and expansive Gaelic football.
That Donegal will offer the sternest test of this mesmerising and powerful attacking philosophy, and see just how far this group has come since 2011, is unqestionable.
With the attacking triumvirate of Michael Murphy, Colm McFadden and Paddy McBrearty, Donegal certainly possess the ability to ask questions of the Dublin's full-back line if their counter-attacking game-plan gains traction.
But while the threat to Dublin's ambitions is clearly evident, to my mind this test is somewhat tempered when you consider the internal battle that exists within this Dubs squad to secure a jersey, let alone a starting place.
My guess is that similar to the Kilkenny hurlers at the height of their powers (not that they've gone away) the Dubs 'A' versus 'B' games are close to being as competitive as any championship encounter. And given that Rory O'Carroll, Philly McMahon and Michael Fitzsimons have been facing up to the likes of Cormac Costello, Dean Rock and Eoghan O'Gara on a weekly basis since early May, you could hardly say they've had it easy in training.
While the element of surprise from 2011 has passed, the fear I do hold would be around how well Dublin cope with the possibility of 29 players being crammed inside Donegal's half of the field.
A quick scan of the scores conceded in 2011 and '12 illustrates just how difficult teams have found it to break down this defensive cordon, with Donegal's concession average being nine (2011) and 11 (2012) scores.
There was a significant drop off in 2013, the year after their first All-Ireland in 20 years, but the average is back to where McGuinness would expect it, at just over 11 scores per game, and interestingly in the 17 championship games across those three years they have never conceded more than one goal per game.
This year alone, however, Dublin have hit nine goals in four matches and on average are hitting 24 scores per game, so it is clear that something has to give between these two contrasting styles of football.
But this is where the words from Waterford ring true. If Dublin bring their relentless high-tempo, pressing game they have the ability to stop any Donegal momentum before it gets going and force McGuinness' men into considering how they break down Dublin's best form of defence, their attack.
So for Dublin to progress to the All-Ireland decider ideally they will strike early to put Donegal on the back foot and sow some doubt about their system into their minds heading in for half-time break.
Should that fail to materialise Dublin must be patient, vary their play and be absolutely disciplined with the back-up cavalry propelling them home.