Former Labor minister Lindsay Tanner hit the book tour circuit this week, stirring up memories of Kevin Rudd's sacking. But was Rudd's departure so unorthodox? Barrie Cassidy says Australian politics is far more unpredictable than the media accepts, and far less routine and orthodox than the public presumes.

Here's a trivia question that I suspect will trip up most Australians.

Of the 11 prime ministers since Robert Menzies, how many first came to office in the traditional way, by winning a federal election?

The majority or a minority?

The answer is four – just four of the 11 since Menzies retired on Australia Day in 1966.

They were Gough Whitlam in 1972, Bob Hawke in 1983, John Howard in 1996 and Kevin Rudd in 2007.

Of the rest, six of them - Harold Holt, John McEwen, John Gorton, Billy McMahon, Paul Keating and Julia Gillard - first made it to the Lodge either by winning a party room ballot or securing the endorsement of the party room between elections.

A seventh – Malcolm Fraser – was uniquely elevated by the Governor General.

Since 1966 therefore, it has been the exception rather than the rule that the people decide who should be prime minister.

Australian politics is far more unpredictable than the media accepts, and far less routine and orthodox than the public presumes.

Yet the most cursory attention to talk back radio will emphatically tell you that voters have a powerful view on this. It is their will that should prevail, and not the judgment of MPs between elections.

The idea – in fact the reality - that the electorate simply chooses local members and the parties themselves chose the leaders is something that seems to be lost on so many, particularly as election campaigns are increasingly built around personalities.

A similar sentiment was on display during the failed push for a republic. The overwhelming sentiment was that if the system had to change, then the people wanted a say; they wanted a directly elected president and not one appointed by the parliament.

It is that fiercely held notion that in part explains why the sacking of Kevin Rudd in 2010 refuses to go away; why, two years after the event, it can be revived as front page news at the drop of a hat.

None of the other changes provoked the same reactions, apart from the dismissal in 1975. That is because most are not comparable.

Holt, McEwen and Gorton came to the job in unavoidable circumstances. Keating won after Hawke had served four terms.

The one analogous situation was the decision in 1971 to replace Gorton in his first elected term, with McMahon. But even that came after the Coalition under Gorton had suffered a 7 per cent swing against it in the 1969 election, reducing its majority from 45 seats to just seven. Gorton, initially popular, had lost his appeal and the mid election switch did not come as a bolt from the blue.

The point is that whenever the public is reminded of the midterm sacking of Rudd, you can almost feel the unease, the stirring of discontent. It happened again this week when former minister, Lindsay Tanner, broke his silence and spoke out against the move.

It will happen again when Rudd's former parliamentary secretary, Maxine McKew, releases her book in November.

It matters not that Tanner is one of Julia Gillard's long term internal party rivals, at one stage working hard to block her initial entry into the parliament.

While actively involved in politics and since then through the publication of his first book – Sideshow – Tanner has demonstrated an ability to tap the electorate. They see him as a straight shooter.

It is then difficult to argue against his analysis that Rudd should not have been sacked, and that it happened because the party essentially panicked over poor polling.

Difficult, but not impossible. So here goes.

Rudd lost his leadership because of a bottom up rebellion in the caucus. Ministers, many of them, had no idea that the coup was brewing. They were kept out of the loop because they were part of the problem. Because Rudd had assumed total control over the makeup of the ministry, few of them would stand up to his worst excesses. Caucus members were only too conscious of that.

As I wrote in The Party Thieves,

The polls provided the excuse, but they were just an excuse. So many in the parliamentary party didn't like Rudd, right from the start, and it only got worse. Some straight out detested him. Dozens of leaders have survived slumps in the polls, and been given every chance to recover. Others will in the future. Rudd was treated differently because he was different : autocratic, exclusive, disrespectful and, at times, flat out abusive. There was no goodwill. As one backbencher put it: 'The fear of defeat did begin to outweigh the fear of Rudd's fury and persecution. And finally the moribund democratic instincts of Labor began to reassert themselves.

When the move came, there was very little arm twisting to be done. Never before had the numbers tumbled so quickly at just the whiff of a challenge.

That dramatic shift in support was built on far more than "panic" over polling. It was a combination of policy failures, drastic reversals, bullying by staff of elected MPs and a total disregard for the party and the caucus.

Neither is Tanner necessarily right when he says that Labor would have won the election had they stuck with Rudd. Quoting John Howard as a source who shares the same opinion doesn't carry much weight either. That is a self serving view.

It is impossible to say either way. However, Rudd's polling, published and internal, was falling, and fast. The electorate had figured him out. His decision to walk away from action on climate change after declaring it the greatest moral challenge of our time would have cost him dearly in a campaign. There is no point in arguing that others persuaded him to ditch his policy. He was the leader. He would have been held to account. The advertising would have been punishing.

Another of Tanner's arguments appears sound enough on the surface. The party, he says, should not back away from reviews and analysis. But Tanner offered no solutions, just retrospective criticism of the party for sacking Rudd. Simply reducing the whole thing to public bloodletting and self obsessed dialogue is counterproductive for any political party.

In any case, didn't the ballot in February this year (Gillard 71 – Rudd 31) amount to a reasonable review of the events of June, 2010?

That ballot was won so convincingly by Gillard in part because key people did what they should have done, but were inclined not to do, 18 months earlier – they finally went out and brutally and without ambiguity explained to the electorate why it was that they moved against a sitting prime minister in the first place. Until then, the electorate was at a loss, never able to get its collective head around it. The sense from voters was that they had been denied a say.

That sense dissipated somewhat after the public airing of the issues and the ballot in February. It was better understood.

Now that sense of detachment from the process will rise again. Tanner has struck the rawest of nerves in the community.

None of this will be as damaging to Prime Minister Gillard as the leaks were in the 2010 election campaign. They denied her majority government.

But Tanner's book, and the country-wide promotion that goes with it, could at least temporarily stop in its tracks the gradual momentum that the Government had been building up for much of the year.

Barrie Cassidy is the presenter of ABC programs Insiders and Offsiders. View his full profile here.