South Africa A 136 and 35 for 2 trail England XI 414 for 6 dec (Cook 126, Root 117, Stokes 66, Hales 56, Maharaj 4-129) by 243 runs

It is only the natural pessimism of England cricket followers - pessimism ingrained by years of hurt and humiliation - that could provoke the thought: the early part of this tour to South Africa is almost going too well.

A day after the last piece in their bowling plans fell into place, England saw their batsmen take the chance to find some form and confidence with a series of encouraging performances. Alastair Cook and Joe Root, with imperious centuries, dominate the scorecard, but the contributions of Alex Hales, who made an increasingly composed half-century, and Ben Stokes, who bullied the bowling, were equally pleasing.

Yet, just as you know that things are about to go horribly awry in the Eastenders Christmas Special when Dot Cotton says "Now nothing can stop this being the best Christmas ever" - a phrase that usually precipitates a fight, a shooting, a divorce and the appearance of Danny Dyer - the sense remains that life is about to become substantially more difficult. Dale Steyn, Hashim Amla, AB de Villiers et al. will surely offer sterner tests.

But while it has become customary in recent times for touring teams to be presented with relatively weak opposition ahead of Test series - and it is true that, in Potchefstroom, England were up against a side some way below the standard expected in international cricket - that is not the case here. This South Africa A side contains several men who can consider themselves realistic options for the national team in the coming weeks, yet England have established a vast first-innings lead and will go into the first Test with confidence soaring. Every one of England's Test top six has now made a half-century at least on the tour.

To further raise England's spirits, Steven Finn reported no repercussions after his exertions on the first day of this match and James Anderson looked fine while bowling in the middle during the intervals. Hales, too, reported no discomfort following a blow on the hand on the first day and Moeen Ali completed the day by producing a beauty to turn through the gap and bowl Reeza Hendricks.

The one minor concern is the lack of time that England's No. 7 and No. 8 - Jonny Bairstow and Moeen - have had in the middle. But, by the parameters of modern tours with their lack of preparation time, this warm-up period could hardly have gone better.

Especially pleasing was the performance of Hales and Cook. England have struggled for a consistent opening partnership since 2011 and while some concerns remain about Hales' ability to deal with the short ball or cope with the consistency of Test-class bowlers who will provide few scoring opportunities, he came through this test impressively in helping Cook post 112 for the first wicket.

After an uncomfortable start on the first evening, Hales unveiled a series a glorious drives - two through extra cover and one through mid-on had the small crowd purring with pleasure - and generally ducked the short ball without too much trouble. While the manner of his dismissal - leaving a straight one for the second time on the tour - was not ideal, this was a generally encouraging effort against bowlers who were, initially at least, impressively hostile.

Cook, meanwhile, looked almost completely untroubled in recording the 51st first-class century of his career. He has already scored more Test runs in a calendar year than any England captain in history. If he manages another 125 in the Boxing Day Test, he will surpass the record for any England batsman (1,481) set by Michael Vaughan in 2002. Both will have played 14 Tests in a year.

He looks in the form to do it. Since being relieved of the ODI job, he has rediscovered much of the consistency that earned his reputation and here, as he seized on anything fractionally short or on his legs, he looked to have developed a slightly more aggressive approach. He hit two sixes, one a slow-sweep off a long-hop from left-arm spinner Keshav Maharaj and the other a pick-up pull off Marchant de Lange to bring up his century.

De Lange may have lost just a little of the pace that rendered him such an intimidating prospect a few years ago - his action is markedly smoother - yet he remains unusually hostile and gained a bounce others could not. He has, no doubt, the class to play more Test cricket but it is hard to see how, bowling generally three and four over spells, he could fit into a three-man pace attack.

While Nick Compton, beaten by a quicker delivery from the persevering Maharaj, and James Taylor, chipping a return catch back to the same bowler, missed out, Root looked in sparkling form. It is true that the pitch had eased and the bowlers tired by the time that he and Stokes, whose half-century took just 41 balls, added 104 in just 15 overs but the manner in which he swept, skipped down the pitch to drive and pulled when the seamers dropped short suggested he, too, was ready for the Boxing Day tussle.

South Africa, as the world's No. 1 rated side, remain favourites, but England have a confidence that belies the fact that they have lost three of their last four Tests.

George Dobell is a senior correspondent at ESPNcricinfo