The old one about form book holding no truths in cases of local rivalries doesn't cut it here.
Indeed, it's been a while since the aforementioned tome told such contrasting stories about the protagonists in Munster's great football duopoly.
Cork struggled to paint themselves into the promotion picture this spring, scored just four goals in seven matches and threw away a couple of big leads.
Kerry won Division 1 and beat the team that hadn't lost in two years in the final - the Dubs.
Cork stumbled past Waterford by just a point, the closest the Déise have come in such a match since they last beat Cork in 1960.
Then they had all of one point to spare again against a Tipperary team that was both severely depleted and totally lacking in the rudimentary requirement of someone - anyone - to win a kick-out.
It's also 22 years since Cork beat Kerry in Killarney, so that whole not having Páirc Uí Chaoimh open in time thing couldn't have been more inconvenient for the county's footballers.
To be fair to Cork, it can't have been easy to digest a first half performance as bad as that which they served up against Tipp but they did.
Some of their leaders stood tall and even more impressive was their ability to respond to Conor Sweeney's late, potential game-deciding goal with one of their own directly afterwards.
They performed best when the situation took on its bleakest look.
Paul Kerrigan was a constant beacon but there was something very disjointed about Cork's movement in the first half and he was frequently left to furrow alone.
Clearly, there's much more to Cork than they have served up so far this year but quite why they can't unlock it is starting to become a mystery.
The problem for them is that Kerry don't look like the sort of team that will hang around and wait for them to figure it out.
James O'Donoghue lit up Cusack Park in Kerry's own lacklustre Munster semi-final win and for followers of the Kingdom, the prospect of the 2014 Footballer of the Year and Paul Geaney both fully fit, in-form and working in tandem in Croke Park is the stuff to drool over.
"It was our first game in ten weeks, and it took us 35 minutes to get going," explained Éamonn Fitzmaurice this week.
"You also must realise Clare are a very good team."
"Then we gave away that penalty, we didn't have the best of starts, things going against us, but as I said afterwards, I was pleased with the resolve and character of the players, they dug in and we won by six, probably should have been a small bit more.
"You have to be happy with that."
Clare got close and when Donnchadh Walsh was sent off, might have fancied their chances.
Late on, Fitzmaurice brought in his 'closers' and it's in this department - although not exclusively - that his team has a serious advantage over Cork.
Kieran Donaghy, Stephen O'Brien and Johnny Buckley all changed the dynamic of the Kerry attack while Bryan Sheehan made sure no free within 55 yards would be passed up, hence no value in cynical fouling for the opposition.
Throw in Darran O'Sullivan and one of Jack Barry or Anthony Maher you have yourself a potent bench of huge talent, massive big-game experience and significant variation.
By contrast, Peadar Healy's use of his bench in Cork's last two games was out of last-ditch desperation.
In theory, Cork are talented enough to take Kerry on and puncture their defence with hard running but down the stretch, there's no denying the home side have more depth.
And this one might not even go that far.
ODDS: Cork 11/2, Draw 14/1, Kerry 1/7