As the provincial championship structures take cover once more and the general imbalance in Leinster between Dublin and the rest inevitably dominates the conversation, it's worth considering a couple of historical facts.
Some 55 years ago, almost to the day, Dublin beat the same opponents by 26 points (10-13 to 3-8) in a corresponding quarter-final.
Allowing for 'inflation' - fitter, stronger, faster Gaelic footballers scoring and creating more scoring opportunities - what would a 26 point beating translate to in modern currency, 40 points maybe?
Within eight years of that defeat Longford had won their one and only Leinster football title, beating Dublin by a goal in the quarter-final.
Not much consolation now after a Dublin victory that was their highest in their current cycle of dominance in the province, dating back to the 2005 championship. Only the 2008 Leinster final win over Wexford by 23 points comes close.
Perhaps it's difficult right now to see beyond a province shrouded in so much blue. Perhaps it's moving past the point where we can call this sequence of success merely cyclical, where we can sense history as an irrelevance.
But it's something small to cling to as they contemplate the scale of their reversal.
A change of venue surely would have pared the scoreline back to more reasonable terms.
But once Longford reconciled to take on the champions, man-for-man in their own back yard and invite them to exploit the space, the margin always had the capacity to hit 20 points and beyond.
Not even a downpour during the preceding hurling match could compromise Dublin's slickness.
It was, admitted Longford manager Jack Sheedy afterwards, something neither he nor his players wanted to do.
If they were going to lose, they might as well do so on a point of principle. So the temptation to park the bus and manage the scale of defeat a little better was spurned.
"Don't believe in it. Don't like it. I think its horrible to watch," he reflected. "As a spectator sport, its called football so lets go play football to the best of our ability. If we had done that with our lads, what would they have gained out of it? Very little," he said.
"They got to experience playing against one of the best teams in the country, suffered heavily against them, but putting 15 guys behind the ball was not going to improve how they play football so no, I wouldn't have wanted to do it. And they (the players) wouldn't have wanted it either.
"We don't have the physical resources to do what some teams can do in Croke Park with Dublin. We felt it was better that we try and go with what we we're doing all season and play to our strengths. Some of it was quite good."
Jim Gavin (right) hadn't expected anything different from his old Dublin colleague.
"Jack would be more of a traditionalist like myself. I have looked at his teams and I have followed them in the club game, some of the teams he has played. He plays a very traditional game, like myself, so I was not surprised."
Thus the game had a rather gentlemanly feel to it throughout. Longford picked up a couple of yellow cards, their midfielder Kevin Diffley was flashed a black for his attempted pull-down of Kevin McManamon in the build-up to Dublin's second goal from Paul Flynn on 28 minutes, and the game produced just 25 frees by our count, 13 to Longford though referee Conor Lane used the advantage rule liberally and almost always to good effect.
But the crowd of 33,544 were largely disengaged and, in that sense, the execution of skills and movement by Dublin was largely overlooked.
The road-block they hit against Donegal last year has rendered these displays at this stage of the year largely inconsequential in the public eye.
And that creates an image problem for the competition which concerns Sheedy who has added his voice for serious change.
"Who is going to get within 15 points of Dublin?" he asked. "Possibly Meath are the only team that are equipped to do that within Leinster.
"So you have a two-tier Championship and two teams, then nine others. There's no benefit to that. You have a similar situation in Munster.
"I think we have a fantastic game, a fantastic product - as people like to call it - but we're getting away from... we're losing people going to the games because it's not attractive, it's not interesting.
"There's nothing big there to come and watch and it's disappointing because we've gone away from the traditional values of what the game was about. I think we really need to review it."
The signs were ominous for Longford when they lost their first seven kickouts and fell 1-5 to 0-0 behind after only eight minutes, the goal from Dermot Connolly struck with conviction and class. Longford steadied themselves, three points from Rory O'Connor invaluable in that spell, as a bit of complacency set in with Dublin.
But the fluid movement and inter-play was almost always refined and the move for that second goal from Flynn was as good as any they produced - Connolly, Dean Rock and McManamon combining in the build-up. Bernard Brogan looked sharp and eager as he helped himself to 1-6, a return of six points from seven shots a far better percentage than he enjoyed at his peak between 2010 and 2013.
Brian Fenton's swift rise to prominence this year was embellished with a productive display and, right now, he looks like Dublin's most consistent midfielder over a full 70 plus minutes, while Ciaran Kilkenny buzzed around the middle and was involved in plenty, though a couple of stray second-half passes let him down.
By the break Dublin led 2-14 to 0-8 and the misery for Longford continued with just two pointed frees advancing their tally in the second half. The final whistle couldn't come quick enough.
Gavin whipped off McMahon and Connolly at half-time citing club involvement next weekend. But was Connolly's over-elaboration when he slipped just after the Flynn goal a factor in his removal?
Two goals between the 51st and 52nd minutes from Rock and Brogan squeezed them tighter and threatened further embarrassment.
But the sting was somewhat taken out of Dublin when the match was held up for almost six minutes due to an unfortunate collision between Longford's Ross McNerney and Pauric Gill and Dublin's Darren Daly. McNerney was stretchered off and transferred to the Mater Hospital afterwards with a bad facial injury.
Scorers - Dublin: B Brogan, D Rock (2fs, 2 45s) 1-6 each, P Flynn 1-3, C Kilkenny 0-3, D Connolly 1-0, K McManamon 0-2, B Fenton, P McMahon, P Andrews, T Brady, E Lowndes all 0-1 each. Longford: B Kavanagh 0-5 (4fs), R O'Connor 0-3, P Collum (45), L Connerton 0-1 each.
Dublin - S Cluxton 7; P McMahon 6, Davy Byrne (Naomh Olaf) 8, J Cooper 7; D Daly 8, J Small 7, J McCaffrey 8; B Fenton 8, D Bastick 7; P Flynn 8, C Kilkenny 8, D Connolly 6; D Rock 7, K McManamon 8, B Brogan 9. Subs: T Brady 6 for Connolly (ht), M Fitzsimons 7 for McMahon (ht), MD MacAuley 7 for Bastick (45), P Andrews 7 for Flynn (52), E Lowndes 7 for Cooper (55), A Brogan for Brogan (60).
Longford - P Collum 7; D Brady 6, C Farrelly 6, B Gilleran 6; C P Smyth 6, B O'Farrell 5, D Masterson 7; M Quinn 7, K Diffley 5; R O'Connor 7, R McNerney 5, P Foy 6; B McKeon 5, B Kavanagh 6, R McEntire 5. Subs: L Connerton 6 for McKeon (17), D Reynolds 6 for Diffley BC (28), A Rowan 5 for Smyth (48), P Gill 5 for O'Connor (52), F Battrim 5 for Masterson (57), E Williams for McNerney (70).
Ref - Conor Lane (Cork).