There was a time when people believed the world was flat and, later on, that smoking was good for you. Values, once taken as immutable, are sometimes made to look absurd by time.
Might it be the same with technique in cricket?
In the not so distant past, it was an oft-repeated adage that "cricket was a sideways game". But as Alastair Cook
proved at The Oval, times change. And a more open-minded - and open-faced - stance can sometimes make all the difference.
Cook first started using Gary Palmer
as his batting coach in the early months of 2015. He had, at that stage, been dropped from the ODI side and was without a Test century for two years. Graham Gooch suggested a trip to Palmer, a former Somerset allrounder (and, inevitably, the first "new Botham"), in something approaching a last throw of the dice.
The visit turned his career - and his stance - around. Palmer argues that a more open stance allows batsmen to play straighter, increase their scoring opportunities and improve their balance. It is, he insists, infinitely preferable to the sideways on stance that can often result in bat movement being inhibited by the presence of the front leg.
It has certainly worked for Cook. He scored two centuries in his next four Tests and, while this innings was the first time he had recorded a score of 50 or more in the first innings of his last 12 Tests, there have been pretty regular second-innings runs.
So while Cook, confident in the location of his off stump, was able to deal with the movement gained by an excellent South Africa attack here with relative ease, his colleagues were unable to cope. Cook, leaving the ball just outside the off stump with excellent judgement, seduced the bowlers into pitching straighter, tucking them off his hips as a consequence, and finished the day unbeaten on 82. The next-highest contribution was 29.
Had Jennings been caught on 0 on debut in Mumbai, he would have scored 99 runs in nine Test innings
Compare his method to that of Dawid Malan
. Now Malan was understandably nervous. He is, at 29 years and 327 days, the oldest specialist batsman to make a Test debut for England since Steve James in 1998 (and before him Alan Wells in 1995) so he knows his opportunities may be limited. And he sure did receive a terrific delivery from Kagiso Rabada - quick and swinging late - to defeat him.
But in his short stay, he demonstrated the limitations of his sideways technique. He missed out on several deliveries on his pads and thigh - his body closing off his bat from taking advantage and his head falling to the off side and leaving him poorly balanced - and, when that wonderful delivery came along to dismiss him, he wasn't in optimum position to deal with it.
It had been the same with Keaton Jennings
. Standing tall and sideways, he is unable to get as far forward or play as straight at those deliveries pitching on middle and angled across him. Were he to open his stance just a little, he might find it easier to access those deliveries with a straight bat without having to play around his body. He would also increase his scoring opportunities - particularly hitting down the ground - and might well have a better idea of which balls to play and leave as his balance improves.
He is now averaging 8.80 in this series. Had he been caught on 0 - as he should have been - on debut in Mumbai, he would have scored 99 runs in nine Test innings. As it was, he went on to record a century on debut and win a prolonged run in the side. Unless he is able to look more convincing in the second innings of this match, though, that run may well come to an end.
It might be considered encouraging, however, that Palmer feels his faults could be corrected in a single net session. And while he does not comment on the identity of players who approach him, he does confess he "would love" to work with several members of this team.
There's an inconsistency here, too. It is common for right-handers to open their stance when facing left-arm seamers operating over the wicket. So it stands to reason that left-handed batsmen should open their stance to deal with right-handed bowlers operating over the wicket.
Not that Cook has limited his use of an open stance. He is the same now with right-handers (such as Morne Morkel) bowling round the wicket and spinners of all types. While traditional coaches argue that the back foot should remain pointing square of the wicket, Cook's now points in the direction of cover, or even extra cover, with his front shoulder pointing towards mid-on. There were few runs in the 'V' on Thursday - the ball was nipping around and he was reluctant to push forward - but he has, in recent months, started to hit the ball back over the head of spinners and drive the seamers straight back past them with much greater regularity.
Might it be telling that Cook has honed his technique outside the ECB coaching system? He continues to travel to Palmer's nets near Oxford for sessions - he was there over the weekend - training, drilling and honing his game. He pays for the sessions out of his own pocket. Given the success he has had, it seems odd that Palmer's request for access to more England players, or for more involvement within the ECB system, continues to fall on deaf ears. And if England don't use him, it surely won't be too long before another nation does.
This reluctance to accept new ideas extends to bowling, too. In recent weeks, Dr Paul Felton - a biomechanist who works with the ECB - has been delivering lectures on the characteristics and indicators of pace bowling. They are, by all accounts, excellent.
But Ian Pont, the freelance fast-bowling coach, provided strikingly similar evidence to the ECB almost 20 years ago. Yes, the jargon is different, but Felton's conclusions - based upon scientific research and designed to help the next generation of bowlers find more pace and control - amount to something very similar to the 'Four Tent Peg' philosophy Pont has been preaching for a generation. He has, at times, been dismissed as a dogmatic, one-size-fits-all maverick. History may well reflect that he was simply ahead of his time.
"I've had 25 years of people telling me that one size doesn't fit all," Pont told ESPNcricinfo on Thursday. "And that there's no template for teaching fast bowling. Yet here we are with exactly that."
Alas, it seems in English cricket, it still seems the face has to fit before the voice is heard. And the likes of Palmer, with his West County burr, and Pont, with his methods threatening the ECB hegemony, are too easily dismissed when they should be embraced.
George Dobell is a senior correspondent at ESPNcricinfo