Seven defeats in ten winless Tests, during which he has scored a meagre 420 runs at 22.10: the wolves are circling Alastair Cook.

His leadership through the post-Ashes transition was always going to be put under pressure - rightly or wrongly, the excision of Kevin Pietersen was perceived as his doing, while Giles Clarke's ludicrous "right type of family" comments chafed at public sympathy - but it is his tactics that have invited the closest scrutiny, for their "naivety", "rigidity" and "timidity".

Shane Warne excoriated Cook's day four Headingley performance as the worst he'd seen in 25 years, while TV commentary boxes not light on ex-England captains have been regularly bewildered by his decision-making: six boundary riders for a No. 10 facing the new ball; opening-session bouncer barrages on a greentop; redundant fine legs and absent third men. Nasser Hussain labelled it "reactive", the clear implication being that Cook is unable to read the game's unfolding present until after it has happened, which is too late. Either that, or he is unable to impose his will on senior players.

Even so, there remains much goodwill out there. Cook was lauded for creative, "funky" field placings on the turgid Trent Bridge pitch - most vociferously, it has to be said, by Stuart Broad and Jimmy Anderson, in what felt like a slightly forced show of support. Yet even there, as at Lord's, it was assumed that England's post-prandial improvement was someone else's doing.

In a balanced and sympathetic piece in these pages, it was suggested that much of the criticism has been for "mundane factors. It has been for his conservative field placings and safety-first declarations… factors that constitute a relatively small fraction of the role of captain".

Are they really so minor, so mundane?

While cajoling a team's personalities through tough sessions in the field is evidently fundamental, international cricketers should be those least in need of motivation. Yes, he needs to score runs, but that's as a player. And media duties are a chore - one Cook has faced with great dignity, if some discomfort - but they cannot be more significant than how he arranges his fielders and uses his bowlers.

Let's make no bones about it: it's in the field that the captain earns his corn. If you're making "daddy hundreds" yet dropping tactical clangers, your team will quickly lose faith in your judgement, and thus your leadership. And the opposite is true, as demonstrated by Mark Taylor when in a similar trough. (Taylor is an "allrounder" for Warne, due to his tactical acuity.) The continual decision-making, the micro-adjustments, the details that can change the course of a session, a match, a series, a career, a life - surely that is the nitty-gritty of captaincy, the wellspring from which authority flows.

Perhaps it is less the art of captaincy than it is the geometry: a real-time computing of information - the bowler's release (angle, height), line, and movement (swing, seam); bounce from the surface; batsman's grip (soft or hard hands, closed or open face); his intent; his response to the unfolding match situation - to create a mental picture of the likeliest places for the ball to go. With the very best captains, it looks automatic, even when they are themselves unsure (cf. MS Dhoni). They form a quick snapshot, then set fields that demand of this particular batsman, in this particular situation, a greater degree of risk (trying to hit it those three yards straighter or square), pulling them out of their comfort zone in the search for opportunity, the margins determined by their aggressive instincts.

It is the split-second retrieval structure referred to by Matthew Syed, in Bounce, as "chunking": condensing information in a mental representation that gives an apparently instantaneous evaluation of a complex state of affairs. He cites an experiment in which members of the public and chess grandmasters were shown 25 identical match configurations. As expected, the experts greatly outperformed the laymen. However, when the experiment was repeated, this time with totally random placement of pieces on board - i.e. not in familiar arrangements - the grand masters were no better at recalling the location of the pieces.

"What was going on?" Syed wonders. "In a nutshell… when chess masters look at the positions of pieces on a board… their long experience of playing chess enables them to 'chunk' the pattern with a limited number of visual fixations… It is a skill derived from years of familiarity with the relevant 'language'."

In cricket, of course, the technical cues of opposition players are largely provided by exhaustive video analysis, by dossiers. Subtleties are illuminated. Detailed information is taken on to the field. Yet the game has a habit of eluding prescriptive knowledge, and situational cues must come either from first-hand experience, or from engaging with the game exactly as would a captain.

Ricky Ponting revealed in a recent interview that despite having negligible leadership experience when handed the ODI captaincy, he nevertheless felt ready because as a player he had always thought about the field placings and bowling changes he would make. Was this equally true of the young Cook, or was he focused on batting? Is he too reliant on the backroom, his mental snapshots too formulaic? Is he deficient at chunking, at reading the game?

At Lord's, while debating with Andrew Strauss the precise positioning of Ravi Jadeja's leg slip for England's left-handers, Nasser Hussain said, "It's a game of angles". Geometry. Yet this came with a caveat: it is not a game of absolutes, only educated guesswork. Solving puzzles. And here, plans that work are one thing, hunches a different joy altogether.

Perhaps, then, Nasser was amiss to criticise Cook for being reactive - one tinkers as the picture emerges into focus, as it changes (and, to paraphrase Jean-Paul Sartre, everything in cricket is complicated by the opposition). The bigger mistake was not to have read the game - to have shaped the game - more astutely in the first place.