You are going to hate this, but the South Australian Liberals — and especially leader Isobel Redmond — have just demonstrated why the old cliché that a week is a long time in politics won’t go away. It keeps on being proved.

Redmond started the week basking in the glow of having, after only eight months in the leadership, brought her party back from the wilderness in the March 20 election. Not much more than a week later she’d dumped her deputy and then been rolled in the party room on her preference for his replacement.

So the new deputy is the leader Redmond succeeded last July, Martin Hamilton-Smith; the new shadow treasurer will in all likelihood be Iain Evans, the previous (yes!) leader who was rolled in April 2007 by Hamilton-Smith.

For most of the Adelaide media, it was all too easy: this was a trigger for a revival of the internal warfare that has wracked — and for a good deal of the time, wrecked — the SA Liberal Party. The main alignments in that strife are symbolically represented these days by two state front-benchers, Vickie Chapman and Iain Evans, both of them second-generation pols. (For federal correlates, read Christopher Pyne and — still — Nick Minchin.)

In practice, the result, with Hamilton-Smith in the deputy’s seat, probably represents the party’s best hope of continuing the containment of that warfare — which got under way during Hamilton-Smith’s leadership and was plainly accepted by the voting public in the short-lived leadership team of Redmond and her deputy Steven Griffiths.

Still, Isobel Redmond will remember it as not one of her best weeks. Here’s how it unfolded.

On the third weekend in this blue-moon March, the Liberals, led since only last July by the Redmond-Griffiths pairing, had the moral high ground: they’d won 51% and some of the popular vote but still come up short, thanks largely to a daring and skilful Labor defence of some of its most marginal seats. What’s more, they could point to a tawdry (but probably ineffectual) trick by Labor at some polling booths, trying to harvest Family First preferences, which further tainted Labor’s win.

There had been gaffes late in the campaign — one of them, by Griffiths himself, coming to light on the last day of the campaign — but nobody really believed he’d been decisive in the overall outcome. (Griffiths had admitted to The Financial Review the day before the election that there was a touch of spin in a Liberal campaign claim of a $1 billion saving on its hospital re-build proposal compared to Labor’s new-hospital plan — and most people had been thinking the same ever since the big number suddenly surfaced last November.)

On the Monday after the election Redmond said, despite the gaffe, she wanted Griffiths to remain her deputy and expected him to remain shadow treasurer. But within a week the skids were under Griffiths; Redmond was saying she wanted someone more, well, combative (my word, not hers) in his roles, and the word was out that her pick was former leader (once removed) Evans.

Evans is the strong family and factional figure of the Right, who had been leader for only a little more than a year after the Liberals got a drubbing in the 2006 election before being knocked off by Hamilton-Smith. He is the second generation of his family to dominate the Adelaide Hills, and his electorate adjoins Redmond’s.

How did it happen? Well, as the count proceeded, it began to become clearer the Liberals had not done as well in the election as they had hoped. In the end, Mike Rann’s Labor government finished up with 26 seats out of 47, only two less than they had held after the landslide of 2006 which had ended the career of yet another Liberal leader, Rob Kerin. The Liberals finished with 18, which rather took the gloss off the fact that, in two-party terms, they had pulled close to 52% of the vote.

And “Liberal sources” started backgrounding. Whenever the Adelaide media attributes political poison to Liberal sources it’s not all that hard to work out the neighbourhood from which it comes. For example, if the “sources” spray at Chapman you know they are coming from the Right, of which Evans and the former upper house leader Rob Lucas are the pre-eminent old parliamentary warhorses.

Never mind those “sources” almost certainly included people who had been key players in the campaign committee: now they were pointing the finger at Chapman — who had, as all agree, been unduly slow in the last week of the campaign killing off any prospect of challenges by her for a leadership position — and Griffiths.

By the end of the week, Redmond had somehow been persuaded that she needed what Griffiths demurely called “a different skill-set” in her deputy and — surprise, surprise — Evans announced he was running. Redmond’s immediate predecessor in Hamilton-Smith let it be known he thought the team should stay intact; but Griffiths, eventually, withdrew, claiming to sense “a mood for change”.

By then Redmond had made her second mistake. She’d been active canvassing for Evans in the days when Griffiths was hesitating over whether to stand and fight or whether to bow to his leader’s wishes. The depth of that mistake is indicated by what happened in the party room. Leaders should always have someone else doing this sort of work for them, and it should always be someone who can count.

The only announced figures from the party-room ballot for Liberal deputy yesterday were Hamilton-Smith (10) and Evans (eight). But that was the second ballot. Front-bencher Mitch Williams had been knocked out in the first ballot. The best estimate is he got two or three votes. His own would have gone to Hamilton-Smith in the second ballot, so Evans’ original vote may not have been more than six. That’s six out of 18, and common sense suggests some of the six would have included newly-elected members going along with the leader under whom they had just been elected.

Redmond’s third mistake? She stayed in the bunker for two hours after the party meeting before coming out with Hamilton-Smith to face the media.

There’s a lot of tosh flying around the Adelaide media just now about this episode having re-opened the old family feuding pattern of the Liberal Party in South Australia, and this rebuff having eroded Redmond’s authority in her own party room.

But her party room will forgive her these blues, not just because they know she is the best thing going for them as leader but also because one of the reasons they love her is that she is not an internal player. She’s got Easter to reflect on what a good idea it is to stay that way. She will also have time to reflect on the fact that, although she succeeded in getting some work out of old warhorses Evans and Lucas, her reward was to be drawn into intra-party manoeuvring that was both dangerous and doomed.

And Hamilton-Smith will have to use the time working out how to protect her as much as possible from the fusillades that will come her way from the government over this episode. It is one she is not likely to repeat.