Gordon Neill recovered from his war wounds but never forgot the commanders who ordered the offensive in the face of compelling evidence that the outcome would be nothing less than catastrophic.
When he spoke to Neill in 1992, Macdonald was a Christchurch teenager, utterly absorbed by the courage and sacrifice of the men who went to war. For a school history project he found and whenever possible interviewed the thinning ranks of World War I survivors.
Neill told him: "I didn't realise at any time during my service the futility of putting a man like Godley in charge. To think that people like him had the right to send thousands to their deaths."
The officer so despised by the World War I veteran was Lieutenant-General Sir Alexander Godley, a 50-year-old British soldier whose career had survived the Gallipoli calamity of April 1915. Born into a military family, Godley got a taste of active service in the 1899-1902 South African War before arriving in New Zealand in 1910 to set up a territorial army. At the start of World War I, Godley became head of the New Zealand Expeditionary Force.
By the time of Passchendaele, Godley had command of II Anzac, a corps of New Zealand and Australian soldiers which included the New Zealand Division under the command of Major-General Sir Andrew Russell.
Macdonald's new book, Passchendaele The Anatomy of a Tragedy, dissects the leadership of the two generals and gives the ambitious, career-minded Godley a mauling that echoes the bitter memories of Gordon Neill.
"Without question," writes Macdonald, "Godley emerges against the backcloth of the muddy and bloody Third Ypres battlefield as an incompetent bungler who willingly drove his II Anzac to the cusp of destruction."
By contrast Russell, a New Zealander - who later blamed himself for the disaster - emerges from the account with his reputation intact.
Writes Macdonald: "Russell's hands-on, intelligent command of the NZ Division was everything that Godley's command of II Anzac should have been."
From his home near London, 40-year-old Macdonald told the Herald: "It's not that I set out to have a crack at Godley. I started with a clean slate and an open mind."
A former journalist-turned-military historian, Macdonald's book had its genesis in a PhD thesis he completed at the University of London. To reach his judgment on Godley, the author undertook a complex and detailed assessment of battlefield tactics and strategy - the "best practice" contemporary manuals for the theatre of war. He made a careful study of command structures and leadership and reviewed archives including war diaries and correspondence from five countries, including German accounts of the conflict.
To get a sense of how the enemy perceived the war, Macdonald used a professional translator to get a perspective of the battles from the other side of the trenches.
The New Zealander says he's also made his own way across the Belgium battlefields, both in summer and during the bleak European winter, fortified by ham sandwiches and a flask of hot tea. While it was unfair to compare his sense of the reconstruction with the wartime experiences of the 1914-18 generation, "you could feel the biting wind and see the naked ground".
The October 1917 disasters were two assaults in a bigger offensive known as Third Ypres. In 1917, the British frontline stretched around Ypres, a medieval Flemish town.
The Allied strategy involved pushing northeast across rising ground against stout German defensive lines towards Passchendaele ridge. The thrust had a broader goal of securing a vital enemy-held railway line and taking two strategic North Sea ports used by the German navy's surface and U-boat fleets.
The fighting was waged on compact battlefields not much bigger than a New Zealand suburb. But the human cost of pushing just a few hundred metres through barbed-wire entanglements was horrendous, as German snipers picked them off.
To reinforce his point, Macdonald cites a grim battlefield formula which sets metres gained against casualties. Advancing under relentless German fire up Bellevue Spur towards Passchendaele, Godley's corps made at best 700m.
The gain, a dreadful slog through black Flanders mud and in the face of withering fire from enemy soldiers, cost 11,650 New Zealand, Australian and British casualties - a shocking 16.5 casualties per metre gained.
Just a few weeks later, better prepared Canadian troops under Lieutenant-General Sir Arthur Currie took Passchendaele with intelligent use of artillery, infantry and engineering units. They too suffered heavy casualties - 16,041 killed, wounded or missing. For every metre gained, the Canadians had 6.4 casualties.
After the catastrophe, Godley, who had the backing of the Army high command, gilded the lily in his reports: "His letters amounted to well-craft litanies of deceit, although they did contain the occasional kernel of truth."
Macdonald's conclusion is emphatic: "It was Godley, not Russell, who was to blame for sending thousands of New Zealand, Australian or British soldiers to deaths or almost certain injury in the ill-conceived attacks of October 9 and 12."
Bellevue Spur, argues Macdonald, where so many young New Zealanders perished nearly a century ago, "should be better known as Godley's Abattoir".
* Passchendaele The Anatomy of a Tragedy by Andrew Macdonald (HarperCollins RRP $44.99)
