It's easy to forget, but this time last year the cloud over Michael Clarke's batting was over his ability to play long innings. In eight years as a Test cricketer, he had impressed as a bright, aggressive member of Ricky Ponting's batting support crew, dazzling at times, but dazzling only at times.
There was more at stake than self-improvement, which had been Clarke's constant driver. Ponting's career was ebbing, and Clarke was captain. He carried the weight of team now, and also history. The champion batsmen upon which Australia's cricket success had been built all had periods in their careers when they had been not just brilliant, but as dependable as the sun and the moon.
Whatever the final resting place of their batting averages, during these peak periods the champions averaged above 65 and gave an impression of unbowlability. It is the difference between the great and the very good. So what was Clarke to become - a Ponting or a Damien Martyn, a Steve Waugh or a Mark, a Greg Chappell or a Doug Walters?
These daring hopes turned out to be too modest. In the ensuing 11 Test matches, Clarke would bat like Don Bradman. He got to the point where his 50s came without apparent effort and his hundreds, such as last week's at the MCG, were played in a minor key.
His achievements were the highlight of 2012, not just in Australian, but in world cricket. No Australian has ever scored as many as Clarke's 1595 runs in the calendar year and nobody, not even Bradman, has matched his bunch of five singles, three doubles and a triple century.
As impressive as the statistics are, none conveyed the brio of his strokeplay or the quicksilver footwork. He adapted to every situation. He was never boring. A week of Jacques Kallis or Alastair Cook was worth a day of Clarke.
What did it mean for Australian cricket? In the broadest sense, it brought eyes to the game. Channel Nine and Cricket Australia have reported highly satisfactory numbers for Test cricket. Cricket teams are, like economies built by Reagan rather than Roosevelt, constructed from the top down. No rank and file can hold a cricket team together when its captain is a failure, and the public won't turn out to watch a side of worthy Paul Reiffels.
The benefits of Clarke's marvellous run-scoring flowed through his team. Mike Hussey, often coming in to face tired and defeated bowlers, turned into the middle-order punisher. Ed Cowan and David Warner got to develop their Test careers with the safety net of knowing the captain would limit the damage from their inevitable failures.
Warner looks every bit the next champion. Numbers three and four remained unsolved riddles, as Ponting finally slipped away and Shane Watson struggled for continuity and, in a changing team, identity. Clarke's mass of runs did paper over some weaknesses, but that is what runs are for.
It was a good year for Australian fast bowlers, most of whom played Test cricket. The so-called 'rotation policy' was never a policy so much as an ad hoc explanation for decisions juggling the variables of injuries, conditions and form.
It was inconsistent and devalued the cap, but the selectors' brief is neither to maintain logic nor to preserve honour. It is to choose the most capable team to win a match and a series - perhaps the rotation system was nothing more complicated than a shift of emphasis from the former to the latter.
In any case, it was only conceivable because of the glut of high-grade fast bowlers, and that was a good thing. Australia crushed India at home, managed a meritorious win over a stubborn and ornery opponent in the Caribbean, punched above their weight against South Africa and finished by drubbing Sri Lanka. The selectors played in none of the wins, and the one defeat wasn't theirs to claim either.
They shattered Mitchell Starc's dream in Melbourne, but replaced him with the man of the match. The Australian team on Boxing Day one year ago had Shaun Marsh, Ponting, Brad Haddin, Ben Hilfenhaus and James Pattinson. In their place it now has Phillip Hughes, Watson, Matthew Wade, Jackson Bird and Mitchell Johnson.
That is a fair degree of turnover, brought on by a variety of circumstances; to maintain a winning record in such a climate is no mean thing.
Injuries, which rank alongside match referees, umpiring, the DRS and the media as the most boring subjects in cricket, dominated conversation. Why did so many fast bowlers get injured? A cavalry of experts, with and without Cricket Australia laptops, came to a common conclusion: nobody knows.
I, for one, can add that I neither know nor care. I just turn up to watch who's playing. If there weren't injuries, there wouldn't have been a Bird. Or Johnson's dynamic comeback. Or Rob Quiney's nine in Brisbane. If there weren't retirements or family illnesses, there wouldn't have been the chance to see the ongoing eccentricities of Hughes and Wade. If there weren't hamstrings, we'd be complaining about the same old people doing the same old stuff. It's been a good year for the Australian team, a great year for their captain, but it's been something better: it's been interesting.