Why Arsène Wenger has allowed Arsenal board to preside over painful fall from grace

New book reveals Frenchman's gambling instinct led him to accept austerity

“Caviar” is the French footballers' term for a pass from which missing the target would be unforgivable. It is the one Thierry Henry used liberally when talking about Dennis Bergkamp, after the ball which allowed him to put Arsenal ahead in a little-remembered 2-0 win over Celta Vigo, a decade ago. “I moved right, a caviar; I moved left, a caviar. I was squeezed by two defenders, another caviar. Moving deep – another one…” Henry declared.

As the French journalist Phillipe Auclair says in his peerless biography of Thierry Henry, which went on sale this week, those days of Henry, Bergkamp, Patrick Vieira and Robert Pires seem so heady, that "we probably didn't appreciate them as much as we should have," looking back now. Auclair's book covers immeasurably more ground than its title suggests, including the processes of football journalism and the astonishing recent history of the national side, as well as providing a place to grapple with his two conflicting emotions about perhaps the Premier League's greatest player. Auclair loves the player for whom the French nation has shown little love. He is not so sure of the man who detested criticism and displayed rather a lot of calculation. But the book also provides a timely insight into one of the great unanswered questions in English football: why Arsène Wenger has allowed his board to preside over such a fall from the days which feel like distant history now.

Even the transfer fee Wenger paid out for Henry to buy him from Juventus in 1999 – £26.9m in today's money – tells us that he has been a big spender in his time, contrary to the over-simplistic image of him as a man occupying a moral high ground. That size of outlay on a player who had just bombed at Juve after his "season in hell" there, to quote Auclair's chapter heading, was not dissimilar to Liverpool spending 70 per cent of their £50m Fernando Torres money on Andy Carroll last year – and the gamble was no less.

Auclair touches on the gambler's instinct in Wenger which is generally overlooked – "a passionate desire to live life to the full, bordering on recklessness." We see the same characteristic in the way he concentrates on his own team, rather more than tactical consideration of the opposition. "He has a philosophy of the game rather than a tactical awareness of it," as Auclair puts it.

Though history has characterised him as the soul of frugality, his spending certainly contributed to the financial position that a club traditionally renowned for caution found themselves in when they decided to plough money they didn't have into the new 60,000-seater Emirates Stadium. The role of "manager-crusader – hamstrung by financial constraints but spurred on by a passionate faith in youth and what could be built on its virtues," as Auclair puts it, was the only one available to Wenger at Arsenal. The same gambler's instinct led him to accept it.

The portrait Auclair paints of the bonds between Wenger and his players of that era reveals why he has stuck so devoutly to the notion that relationships could transcend money and see Arsenal through their period of austerity. Wenger's forward to Emmanuel Petit's own, excellent autobiography explains the empathy he always felt for the character and bravery of a player who always gave everything and one whose outlook on life he always felt was defined by the death of his brother, Olivier, from an aneurism while he was a teenager. The closeness to Henry was not quite the same but it was always there and the reason why the striker did not depart for Barcelona in 2006.

This did not prevent Wenger from being a very shrewd seller of players, armed with statistics to back up his intuitive judgement. Auclair details how he shuffled players off "with elegance, cunning and a measure of cynicism" – relating how Vieira did not quite understand how he had joined Juventus. "Had it been his decision? Had it been his manager's? Had a trick been played on him? I could see that he bore no grudge towards Wenger but that these questions couldn't find an answer."

Wenger's great old rival Sir Alex Ferguson has espoused the same view as Wenger that finding young players earlier and inculcating a sense of mutual loyalty will insulate against failure. Ferguson likes to relate a fable about migrating geese to reinforce the story and even used the French word for the bird – hirondelle – in telling TF1 all about it last year. "They fly in V-formation but the second ones don't fly. They're the subs for the first ones. And then the second ones take over – so it's teamwork…." the Manchester United manager said

But sadly, such loyalty to the cause no longer holds true. Ferguson almost lost Wayne Rooney two years ago and Wenger failed to spot that, with no trophies on the horizon, a sequence of players just couldn't wait to go. He had seen true Gooners in Pires, Henry, Vieira, Cesc Fabregas and Jack Wilshere. But not in Samir Nasri, Robin van Persie and Theo Walcott, which explains a lot about his stance in Arsenal's latest contract saga.

Wenger predicted in 2007 that the era of austerity, triggered by the stadium move, would be over by the start of the 2009-10 season. Still waiting, he has long since been forced to compromise on his philosophy and buy older players, like Santi Cazorla, Mikel Arteta and Lukas Podolski. His own moral code about the requirement of clubs to be self financing has pushed him into a position where he cannot question a board which – despite his public position on the subject – has disappointed him.

Arsenal sit nine points off the top of the Premier League table already, and only lead today's opponents, Fulham, on goal difference, but don't imagine Wenger is accepting that with equanimity. "He is often described as a 'professor' obsessed with data, GPS and the like," Auclair reflects. But he is anything but a cold, detached logician."

Thierry Henry – Lonely at the Top: A Biography Philippe Auclair. Macmillan £17.99