Recently, while interviewing a current international umpire, it was more than a little amusing to hear that, from time to time, he stands in front of the mirror and practises his "out" signal - don't we all? - taking care to project just the right amount of confidence. Keeping his finger in, you might say.

"You get told to," he explained. "You don't want to come across as wimpish."

Yet neither do you want to come across as some guillotine-wielding martinet. It's a delicate thing, sentencing a batsman to his symbolic death. There's a fairly narrow band of gestural acceptability, much like the range of habitable temperatures on earth. Undoubtedly there have been a few umpires whose executioner's gesture has been authoritarian to the point of being antagonistic.

While all this isn't exactly the stuff of YouTube compilations, a couple that spring to mind are that inveterate not-outer Dickie Bird, whose slightly manic gesticulation was like a grouchy old recluse chasing a couple of scrumpers from his garden, and Rudi Koertzen, who always seemed to relish the whole thing just a little too much. Giving someone out is an inherently mannered act, of course, since you're not born with your own way of doing it, but Koertzen's "slow death" was unbearably pompous and solemn. My own preference was for the apologetic shrug: "I don't want to do this, but you've let the ball hit you on the shin in front of middle stump, so…"

If transmitting confidence is the basis of an umpire's match management, then it's fair to say Bruce Oxenford had something of a mini-meltdown in Mumbai. Four overs after erroneously giving Jonny Bairstow caught behind in England's second innings, he adjudged him caught at short leg off R Ashwin. Bairstow immediately put fist to forearm - body language that we can decode as either absolute certainty or blind self-interest - at which point the camera caught an aggrieved Oxenford grimacing like a man who'd just stirred two spoonfuls of salt into his cuppa. Fack.

It isn't just umpires who have to mind their body language. Evidently it's an important aspect of what players get up to on the field, not least in trying to, erm, influence the umpires. For batsmen who have feathered the ball to the wicketkeeper - or perhaps via the keeper's gloves to slip - it's well worth mastering the butter-wouldn't-melt expression, since our fallible, malleable human perceptual capabilities are continuously susceptible to subliminal cues and micro gestures. If the opposition happens to have no reviews, or you're playing a level of cricket other than international, then this might even win you the match. Whatever you choose to do - scratch your guard, chuckle wryly, anything bar an eagle-eyed stare down the pitch - the basic idea is to immediately convey to the umpire not only that the appeal is wrong but that it is utterly preposterous, possibly even an affront to the game, certainly to their unimpeachable faculties of judgement.

On the flip side, the DRS really ought to temper certain types of excessively excitable appeal - from the "celebrappeal" to the swarm - when they are artfully contrived to con an umpire. "So you're not giving that out then?" "No, but feel free to use one of your reviews." "Well, actually, we don't think it was out either..." Either that or you follow the shamelessly brass-necked deception through to its inevitably self-defeating consequences. You knew it wasn't really out, but because the opposition had no reviews left, you thought that if the umpire were to give it then there'd be no recourse to contest the decision, yet since he didn't give it out, then, even though you know it wasn't out, you're forced to burn a review on it in order to save face, to not be open to the charge of cheating. What delicious psychological knots! It's like the plot to every other episode of Frasier.

Of course, players' body language also bears directly upon the mano a mano struggle of a match - as Shane Warne, that renowned expert in con-man kinesics, used to say: driving onto a ground mid-game, you shouldn't be able to tell who's on top from the body language of the fielding side - but it is perhaps most important of all in the way a captain carries himself (certainly across the long haul of developing a strong team culture as opposed to merely winning a Big Moment or Crucial Session).

Michael Vaughan - English cricket's yin to the yang of Nasser Hussain's perma-prickliness - has admitted that his outward imperturbability was often just an act. But which is better? Was Vaughan's way more congenial to building a winning team than occasionally chucking your toys from the pram, or might calm inscrutability be construed as bloodlessness and passivity?

The answer is that there is no right answer. Communication is all trial and error. An animal displays aggression, but it doesn't know whether the target animal will be cowed and retreat or stand and fight. The meaning of a gesture or sign is thus always more than the simple information it conveys, always tied in to various complex, contextual factors.

Take Virat Kohli. As a batsman, his body language is almost always buoyant. He struts. The more runs he scores, the more he emits what we might call, with a nod to Donald Trump, "swaggerdoccio". Each major innings adds to his stature as a leader. But as Max Weber, the German theorist of the sources of authority, might well have said, a cricket captain must do more than simply stack up runs, no matter how big the pile. He also has to get the best from ten other personalities. And he needs to make good tactical decisions, preferably using strong body language. Bluffed certainty is better than honest vacillation, for things can always be undone. (Once, in a club match, I immediately stationed two short extra covers for Alfonso Thomas. It was a ruse, an attempt to spook him. Later, while bowling me three or four bouncers an over, he observed: "You're a better f**ing captain than you are a batsman, mate." I took it as a compliment.)

There are occasions in the field (less frequent of late, to be sure) when Kohli appears irritable and petulant, particularly with the slapstick efforts of his less mobile fielders. With Ashwin, the kingpin who balances his side, any annoyance is immediately swallowed. With Cheteshwar Pujara, lumbering fielder and good-but-not-quite-as-good-as-me batsman (one who was apparently asked to score at a quicker rate, or, to split hairs, show greater intent), those frustrations are usually left plastered across his face. Such are the complex politics into which bodily gestures are inserted. And make no mistake, they all leave a mark on the collective memory, on the esprit de corps: tolerated today, amid the champagne of victory, yet within the glacial rhythms at which a team culture develops, they may resurface later, the crack having become a fissure.

Either way, it's too simplistic to say that Kohli's gesticulations are "wrong", or that some of his body language is counterproductive. We cannot know what's said behind closed doors, how much carrot juice is used as balm after a beating with the stick. This is a supremely driven and fit man, himself an excellent fielder, evidently troubled by some of his side's lack of athleticism. In that sense, he is merely trying to bootstrap his team toward excellence. Which is good. But to browbeat and chastise people who are trying their best can also be corrosive.

All is ambivalent within cricket's semiotic system - except, perhaps, the umpire's raised finger, even when it's crooked.

Scott Oliver tweets here