He is not the most agile or natural flanker to play the game but his determination, technique, preparation and physical endurance is unparalleled. Exercise books are filled with notes, plans and ideas to support his quest for top-grade performances.
His uncle John "Bigsy" McLay goaded a teenage McCaw to write down his rugby goals and how he imagined he would make the All Blacks. The cautious youngster jotted down All Blacks 2004 but recoiled at signing it Great All Black, jotting down G.A.B instead.
Not long after, All Black coach John Mitchell and sidekick Robbie Deans spotted that talent and picked McCaw for his All Black debut in 2001 against Ireland in Dublin. The G.A.B was on his way.
McCaw's rugby feats are extensive and his appeal is equally broad as he blends his natural charm with extraordinary achievement. He is a bloke with solid beginnings in the Hakataramea Valley who has developed a remarkable aura.
His perspective is real and it was no surprise when McCaw turned down the offer of a knighthood in the New Year's Honours list of 2012 because he was still keen to play on.
The big question will be for how much longer. He and the All Black panel believe a fourth World Cup next year is realistic while the rest of the rugby world wishes for some other outcome.
Self-doubt has rarely been evident in McCaw's career. There were awkward periods through the defeats in 2004, the shattering World Cup loss in 2007 and the difficult aftermath. McCaw was shaken but not as uncertain as he was after three defeats to the Springboks in 2009.
For the first time he wondered whether the All Blacks were not as good as they thought they were, "maybe, no matter what we do, we're not actually good enough," he said.
Around that doubt, McCaw has delivered a vast file of quality work from his man of the match test debut through the series win against the Lions in 2005, against the Wallabies in Brisbane the following year, his feats at the last World Cup, in Soweto in 2012 and leading the side, undefeated, through 14 tests last season.
His influence is reflected in the number of times, frustrated rivals like Quade Cooper, Aurelien Rougerie and Dean Greyling have taken cheap shots to try and hinder his impact and the number of opposition coaches who have accused him of cheating.
McCaw's reaction is to play harder. Even when he wrestled Piet van Zyl to the ground at Durban in 2002 after the spectator attacked referee David McHugh, McCaw did not throw a punch.
He has played flat-out and on the limit of the law throughout. His honours list is extensive, his impact astounding and his place in the top line of All Blacks indisputable.
Statistics
Date of birth: 31 December 1980
Position: Openside flanker
Matches: 125*
Tests: 124*
Test debut: 17 November 2001 v Ireland, Dublin
Province: Canterbury
Franchise: Crusaders
Test tries: 21
Test points: 105