How many mistakes did you make today?

(and let’s get the ‘clicking on this article’ reply out into the public domain as quickly as possible, before commenting wags snap their knuckles trying to be the first to slip that gem below the line…)

Chances are, even if you’re really good at your job – a colossus of asset investment management, or a software solutions analyst of unparalleled renown – you’ll have two to three moments every week where you inhale sharply and hope that no one looks too closely at the calculations you did before lunch when your mind was full of the promise of impending sandwiches. The further chances are you’ll get away with it, because you’re fortunate enough to be someone that the world is paying very little attention to. Embrace your anonymity, and count your lucky stars that you’re not a goalkeeper.

Even the great goalies have a few high-profile moments where their grip deserted them, or they leapt confidently into a patch of air where a dangerous cross empathically wasn’t. As football fans, we accept this though, knowing that the occasional howler is part of the keeper’s trade, and that Banks, Yashin, Zoff, Schmeichel, Kahn, Buffon, Casillas and their fellows in the gloved pantheon would return to tip a fizzer over the bar another day.

But how many mistakes are they allowed before they stop being great keepers? Where’s the tipping point? And has Joe Hart stumbled over that line, ball in hand, conceding a soft equaliser in the process?

From a very young age, Joe Hart was marked out as a Good Goalkeeper. His reputation at Shrewsbury preceded him – knowledge of his sharp reflexes and authoritative yet easy-going presence had all the wise heads that monitor such things nodding in mild astonishment at the shrewd move by Manchester City (who at that point were still the league’s cuddly toy, associated more with haphazard vaudeville than canny footballing decisions) in signing the lad.

Hart’s reputation was partly built on his undoubted talents, and partly on the rabid hunger within the English game for someone, anyone, capable of catching a cross while Lampard and Gerrard stood nearby, pointedly failing to discuss which of them should be sitting while the other bombed on. England hadn’t enjoyed competence between the sticks since a pre-ponytail David Seaman bounced around the goalmouth sporting a haircut that nobody at the time would have believed would be one day looked back on with fondness. The nineties were, in many ways, a more innocent era.

As Seaman’s deterioration into looking like a horse cosplaying as a village postman pushed him into ever-more lobbable positions, he eventually gave way to England’s Era of Uncertainty – an eight-year long period of flaps, fumbles and divots as David James, Paul Robinson, Scott Carson and Rob Green all took turns to drop more bollocks than a clumsy gender-reassignment surgeon.

Hart managed to ascend to the first-choice keeper at Man City during the Thai millions/Swedish managerial lothario era that served as a chrysalis stage between the club’s slapstick and petrodollar juggernaut identities. Even though he had to spend a season of harsh apprenticeship at Birmingham while Mark Hughes allowed Shay Given to frolic in the number one jersey, the sheer tsunami of public spirit, willing the English lad to play, willing him to be good, willing him to solve all the national team’s problems for a decade to come ousted the Irishman and ushered Hart and his newly laden yoke of expectant pressure into the limelight.

And he was good! Consistent, focused and mature beyond his years – unfazed by the sudden influx of serious money, which made the previous influx seem like a crumpled fiver found in a forgotten jeans pocket – Hart was one of the rocks that Roberto Mancini’s first full season was built upon.

But this term, errors have started to creep into his game. Failures to collect, misjudgements in positioning and the latest gaffe, a calamitous spacing of his elbows for Southampton’s second goal that must have sorely tested the Match of the Day editor’s resolve to not add a sad trombone sting to the replays. Roy Keane labelled Hart ‘cocky’ when his mistimed punch led to a Polish equaliser in October’s World Cup qualifier, and it may well be that the young man is starting to believe his own hype.

The counter-argument would be that as Hart plays more games, his number of career errors will rise as a statistical inevitability. The counter-counter-argument would ask why Hart gets the benefit of the doubt while the equally precocious David de Gea gets slated over a similar blunder rate in the Manchester United goal. Could it be that overwhelming public hunger for Hart to be a great English keeper is shielding him from much of the criticism that De Gea – as a foreigner who looks like a beatnik giraffe with no such incipient goodwill – is having to weather?

What is the exact ratio of saves to slip-ups that divides an occasionally flawed genius like Cláudio Taffarel from an occasionally brilliant clown like Fabien Barthez? Is all down to perception? If David James, for instance, had risen to prominence in any team other than a Liverpool squad who epitomised style over substance, would he have carried that ‘Calamity’ tag quite so harshly throughout his career?

For now, England expects Joe Hart to match his youthful promise and capability, and march on into the custodian’s pantheon with his intermittent ricks failing to blemish his magnificence. However, if there are many more flubs like that on display at St Mary’s, then Jack Butland may soon find himself the focus of that ravenous public desire instead.