There's a story that Alex Ferguson once opted against giving a team-talk to his Manchester United players in favour of showing them a short clip of an All-Ireland hurling final.
I'm not sure if it was one of those blood-and-thunder Kilkenny-Tipperary epics, but the wealthy superstars of Carrington were suitably impressed, wincing at the raw physicality on show. When the clip was finished, Fergie just delivered a single sentence.
"They are amateurs," he said, exiting the room without another word.
Ferguson was well educated on the GAA from the time that Kevin Moran was briefly double-jobbing with United and the Dubs. He understood the uniqueness of what we have in this country and the extraordinary levels of preparation our amateur players put in. But the commitment Fergie was so impressed by a decade back has now gone to another level.
Put it this way, the quick turnaround between games in the Super 8s demands an intensity from management and players that lends itself to the whole concept of professionalism in the GAA.
It's a brilliant spectacle for supporters and media, but my God it's asking serious stuff of players. Too much maybe. These men are committing their lives to a cause over this stretch of six weeks, or however long they last in the Championship. And I'd say there's a lot of people over-seeing professional set-ups in other sports who would be startled to see the level this has gone to.
Just think about it. Last week, all the focus will have been on a specific opponent. As of Sunday evening, all of that was flipped on its head. Different opponent, completely different plan. Trust me, the players will have found themselves in an environment of almost clinical preparation.
I don't doubt, for example, that the Kerry players had it drilled into them before they left Fitzgerald Stadium last Sunday of a need to pull the blinds down for this week. To ignore all outside voices telling them how good they had suddenly become.
Monday morning, the analysis teams will have been poring over information for hours and packaging the important stuff into personalised files the players could access on their own laptops. By Tuesday night, everybody will have been fully prepped in terms of information for the weekend looming. The rest of us might still be looking backwards, but not players and management. They'd moved on before they even got off the bus.
There's a real sense that this will be the key weekend for the Super 8s, one potentially separating the wheat from the chaff. It could leave a few dead rubbers for the last weekend.
Yet - bar maybe Dublin v Roscommon - they're all games you'd want to see. Kerry's work ethic was fantastic against Mayo on Sunday, but that should be a given every day. The aim should be to play with that same manic aggression every day you go out. You could see it was in them from the moment a grinning Aidan O'Shea started doing his little war-dance at the throw-in.
That aggression wasn't in Kerry for the Munster final. I still find myself asking why it wasn't.
On Sunday, David Moran reminded me of my own brother Darragh with his high fielding in midfield. But the general press and forward movement in the middle third was outstanding. No aimless lateral passing. Every delivery stamped with purpose. I loved that.
And we saw evidence again that, in David Clifford, Kerry have found a once-in-a-generation talent. At 20, his potential is nothing short of scary. Honestly, I've never seen anybody with better vision. One pass on Sunday was genius, a low ball drilled in while Paul Geaney was actually running towards the terrace.
He knew Geaney would jack-knife back and the low trajectory of the ball caught the defenders flat-footed. Kerry probably aren't scoring enough goals at the moment. But, with that kind of genius, Clifford can be the man to change that.
The essence of Kerry's performance was, above all, about players fronting up and winning personal battles against a team programmed to try and bully them.
I thought Mayo showed all the evidence of a team struggling to keep meeting the obligations of these quick turnarounds. Four games in four weeks seemed, to me, to have taken a toll. Especially considering this Mayo team seem incapable of taking a breather in games. They exist in a high-intensity bubble, no matter who they're playing. The poor movement on David Clarke's kickouts last Sunday had to be seen to be believed. Mayo looked jaded, spent. Their back-door schedule seemed to have taken its toll in terms of injuries and energy.
So I'm inclined to reserve judgement on Kerry until I see what happens now against Donegal. Can they back this up? Mayo were virtually gone from the moment Moran and Adrian Spillane fronted up to O'Shea at the throw-in. Donegal won't be as easily subdued.
Straight away, they have three forwards who will worry any defence - Michael Murphy, Paddy McBrearty and Jamie Brennan. That said, I think this is the game where Kerry can announce themselves as real contenders. It's up to them now.
We all know the ability that's there. But mental toughness is a skill, particularly the type needed to produce a performance week after week, no matter the opposition or where the game is played. Kerry will jump into another stratosphere should they beat Donegal. If they turn up, they can do that.
The other game that intrigues me this week is Cork against Tyrone. Cork were terrific against Dublin, only to find out what so many others found out before them. These Dubs problem-solve while the game is running. No histrionics, no shouting, just deal with what's in front of you. I'm not sure I've ever seen another team in the history of the GAA more accomplished in that department. They don't bend, they don't panic.
That said, I think there's a danger, too, that some of what we think about them becomes self-fulfilling. The cliche now is that they will always crush you in the last 10 minutes, just as they did to Cork. There's a risk that that can seep into players' minds. The idea that this is inevitable. It isn't and it can't be.
In my opinion, teams going in against Dublin need to have it in their mindset that they, too, can kick on in those closing minutes. I still think there are question marks over the defending of Philly McMahon and Cian O'Sullivan.
Cork showed that if you genuinely have a go at Dublin they can be dragged outside their comfort-zone. But just think of the psychological battle facing Ronan McCarthy and his team now.
They put so much into that game and, one week later, it's Tyrone. Real frying-pan into the fire stuff. For all that, I think this is a team that's finally found its identity. That's standing up for itself.
They've got to strike a balance against Tyrone of pressing up on Niall Morgan's kickouts without compromising defensive balance. Easier said than done against Tyrone's runners.
Particularly when you've a man like Cathal McShane on the edge of the square, capable of winning ball even with a sweeper playing in front of him.
McShane has changed Tyrone. He's given them another dimension.
I felt sorry for Cork last Saturday night. They didn't deserve what happened in the last few minutes. Whatever comes their way against Tyrone now, I think it's absolutely vital that Cork turn up again. Show that this is a team growing. But there's a mental as well as physical challenge to these seven-day turnarounds.
That's why I think Mayo might be worried about their game with Meath. Has this schedule finally drained away their famed bouncebackability? Meath will fancy this, no question.
That said, some of us have been wrong about Mayo so many times, I'm sure James Horan will hope to see people writing their obituary now. For what it's worth, my four winners this weekend are Dublin, Mayo, Tyrone and Kerry.
But it's getting harder to read these games because we're slipping deeper into uncharted territory in terms of physical and mental demands.
Funnily, I read a Mick O'Connell quote in the Croke Park match-programme on Saturday night where, having been asked if rowing across from Valentia Island helped his football, his response was something along the lines of 'How would rowing help my football?'
O'Connell was trying to get the point across that football was a pastime to him, never an obsession.
He was talking about a different game.
Some 19 minutes into their enthralling 2016 All-Ireland semi-final, Kerry won their first scorable free when sufficient pressure was applied on Dublin's James McCarthy, forcing him to over-carry.