Stewart's value is indisputable. Since reassuming the two jobs last summer, his batting average in five Tests before the match in Christchurch was 80.5, he had taken 16 catches and made two stumpings. His career batting average in Tests is a formidable 43.14. He is a genuine world-class all- rounder.
But Stewart's figures are enhanced because his versatility allows the selection of five bowlers, which gives England a much greater chance of dismissing the opposition twice and therefore winning. True, this has worked in practice only once so far in his latest incarnation as a man with two jobs but this should not undermine the Theory of Balance.
From the touching faith recently demonstrated, it is tempting to suppose that England have invariably required five bowlers to win Test matches. Well, sometimes and sometimes not. Since Test cricket began its second century 20 years ago, England have played 208 matches and have won 53. The start of this era coincided, of course, both with the Packer schism and the advent of Ian Botham.
He was hardly the first key all-rounder in England sides (Wally Hammond, Trevor Bailey, Tony Greig, to span the generations) but he changed the complexion of the role, hence the constant search since for a new Botham. It was fairly usual in the late Seventies for England to pick three bowlers with Geoff Miller and Botham as all-rounders, either of whom might bat at No 6.
Still, some of England's most thrilling wins in the past 20 years have been achieved with four bowlers, including the all-rounder. At Headingley in 1981, Botham was allied with Bob Willis, Graham Dilley and Chris Old. Peter Willey's off-spin was there as possible support but, as his Test career was restricted to seven wickets at 65 runs each, he could not be classed as an all-rounder. In the match which clinched the Ashes that year at Old Trafford, there were just four men to bowl, Botham, Willis, Paul Allott and John Emburey.
In India in the winter of 1984, four bowlers were enough to win the series 2-1, and in England the following summer the opening victory of another Ashes series was achieved with three bowlers plus Botham. The great man was on the wane and out of the side when England registered their first win against the West Indies for 16 years at Kingston in 1990. The margin was nine wickets and the bowling attack was, in its entirety, Angus Fraser, Devon Malcolm, Gladstone Small and David Capel.
Against Australia in 1993 Mike Atherton's first win as captain came with only four bowlers (Malcolm, Fraser, Steve Watkin, Peter Such - so what a tail it was), with only Graeme Hick in support. Similarly, the historic victory over West Indies at Barbados three winters ago came with four bowlers plus Hick.
Part of England's present desperation for balance has been created by having six batsmen, none of whom even verges on all-rounder status (except, it should be noted in an era renowned for multi-skilling, they are deadly fielders). But the possession of five bowlers is traditional and a comfort to any captain. Stewart achieves that and perhaps if he had been doing both jobs since he played his first Test seven years ago, England would have had a better record (and Jack Russell's international career would have finished long ago).
A word of warning may be in order despite Stewart's recent feats. In all, he has kept wicket in 20 Tests for England, yet they have won only five. It takes more than balance then, and Australia next summer may force further revision, like the need to use a minimum of six bowlers.
Not that England are alone in this pursuit. New Zealand seem desperate to include Chris Cairns, although his batting average is below 30 and his bowling average above it. Mind you, the injury to Lee Germon may have given them balance inadvertently. Adam Parore has resumed as wicket-keeper and No 6 batsman and looks a class act. Germon has a groin injury so he will know what being unbalanced is all about.