Instead, he is polite, warm and wise, happily dispensing the lessons gleaned from commanding the 1st Royal Tank Regiment, serving as operations manager for all three armed services and as commandant of the Royal College of Defence Studies – a college for military high flyers. And that is just to give the briefest summary of his Who's Who entry.
Now 67, he is communications director at Aqumen, the facilities management wing of Mowlem, with a brief to improve the firm's internal and external communications.
Joining Aqumen was a natural move, he says candidly, because it has a lot of defence contracts. "Having sat on the other side of the hill and seen how things operate there, you can help to oil the wheels," he says.
There is much that the construction industry and the military can learn from each other, he believes. Over coffee and biscuits, Walker spoke about organising parades, regimental pride and what construction bosses can learn from General Wolfe.
Let the commander think
The army can teach the private sector a thing or two about efficiency, Walker says, where relentless economising has left too few people to do the work. "There has been a tendency to cut beyond the point that companies are efficient. Too few people are trying to do too much and so people don't have time to really think."
You don’t tell me what the CEO has told you because maybe you can use it to make me look a fool at the meeting tomorrow
And thinking time is important. "In the army, the commander always has a quiet room where he can go and think about the next phase of operations. In industry, executives believe they should be at their desks from 6am to 10 at night. That's not how real achievement happens."
Information is not power
Surprisingly, Walker believes information flows more efficiently up and down rigid military hierarchies than across the supposedly flat structure of the modern company. This is because, in industry, people tend to regard information as power. "You don't tell me what the chief executive office has told you because maybe you can make me look a bit of a fool at the meeting tomorrow, and then I won't be breathing down your neck for your job quite so keenly."
The disciplined military system is less prone to selfishness: "In the army, if the chief of staff briefs me directly, I come out of my office and brief laterally to my peers and downwards to my subordinates, so that very quickly it gets disseminated down the organisation." Firms should put systems in place to disseminate information fairly and rapidly, Walker says firmly.
Where the army falls down
But military efficiency comes at a price. Having no need to make a profit, public organisations do not appreciate the cost of people and time – the two most precious commodities – and this can lead to a wastefulness that business people would baulk at.
Walker is ready with an example. If, as a soldier, he was asked to organise a parade, he says, he would rehearse it endlessly until it was perfect. "But as an industrialist I would rehearse it once and if it was 85% good, I would be prepared to chance it. Another rehearsal would cost me too much. There is a cost-awareness there that the public service generally does not have." This helps explain why public–private projects tend to be so frustratingly slow. "You can see it from the enormous lead times some of these PFI projects have. Companies can go bust just bidding for these things because the public service doesn't comprehend how expensive time is."
You may grumble like mad about your regiment, but if someone else grumbles about it, you punch him on the nose
Love your squaddies
Walker dismisses as "balls" the notion that soldiers are motivated by fear of punishment. In fact, he argues, the army produces inspirational leaders. The key is to care about the people that work for you – something, according to Walker, that officers do naturally since they are directly responsible for all the people under their command. There are no human resources departments in the army.
Walker remembers having to write personally to the parents of all his soldiers. "Now, I'm not suggesting for one moment that the chief executive of a construction company should write to the mothers of all his brickies," he says, "but I think it is important for people to take a genuine interest in the people they are managing.
"It doesn't take you long to find out the birthday of everybody in your department. Make a note of it; it's astonishing the effect it has if you walk in one morning and say happy birthday. It's a gimmick, but it shows you care."
Loyalists and mercenaries
Loyalty is vital in a military environment where your colleagues' lives may depend on your actions. "The regimental cap-badge ethos is a very powerful one. You may grumble like mad about your regiment, but if somebody else grumbles about it, you punch him on the nose."
In the private sector, employees tend to act more like mercenaries, so construction firms would do well to try to generate a little of the cap-badge ethos. "Most companies can find a heritage: Mowlem speaks with pride of John Mowlem and its honourable 180-year tradition. I'm proud to be part of that."
What most impresses Walker about the construction industry is the dedication of the people who are prepared to work hard in adverse circumstances and often for little reward. He admits he did not expect to find that outside the army.