Whichever Treasury or RBA official — or as they’re technically called in the media, boffin – came up with the idea of charging depositors for a guarantee of very large bank deposits, well done. They avoided making bad policy even worse. Charging for a premium should be extended across all deposits. People with brains enough to know that Australia’s banking oligopoly is safe could save some money.

Anyway, enough about that. This heart won’t bleed too much for foreign banks and mortgage trusts.

The real story is about how to bugger up a Parliamentary attack. With the first substantive issue of his leadership yesterday, Turnbull did well for the most part. It was pretty thin stuff — the logical consequence is that either politicians are supposed to slavishly follow the advice of the unelected Reserve Bank Governor, or the latter, despite being independent, is supposed to sit in Cabinet and its sub-committees — but Turnbull sustained the attack for most of Question Time. He hogged the questions — Julie Bishop was the only other person to get one – but he was focussed and on-target sufficiently to visibly annoy Rudd. It was a strong performance.

Toward the end, though, Turnbull badly overplayed his hand. The first hint that they were scratching a bit for where to take the attack came in Turnbull’s fifth question, which amounted to a particularly clumsy attempt to verbal Lindsay Tanner, a case not so much of taking him out of context as transporting him to an entirely different planet. Eventually, frustrated that Rudd was relying on Ken Henry’s assurance as to the views of the Reserve Bank, Turnbull challenged Rudd to sack Henry if the story offered by Rudd didn’t stack up.

This turned what was looking like an honourable draw — a rare thing for the Opposition these days — into an attack on the Secretary of the Treasury, and Rudd gleefully exploited it, demanding Turnbull back Henry during these dark days of economic crisis. Nor did he forget to mention that John Howard had punished Henry for daring to suggest early last year that Treasury needed to be watchful about bad policy — a story that circulated around Canberra for months before being confirmed by Henry earlier this year.

Turnbull has his own problems with Henry. In March, Turnbull claimed Treasury had advised the Government to nominate a dollar figure in its minimum wages submission to the Fair Pay Commission. In a very rare move, Henry issued a succinct press release, without mentioning Turnbull by name, saying “these claims are false”. Asked about the disparity between Turnbull’s and Henry’s version of events, Brendan Nelson happily backed Ken Henry.

Reckon Turnbull is a big fan of Henry?

“You went too far, Malcolm,” called a Labor backbencher, and whoever it was was dead right. You could tell from both Turnbull’s body language and that of his frontbenchers as first Rudd and then Anthony Albanese invited him to publicly back Henry.

Only Phil Coorey and Christian Kerr conveyed what a blunder Turnbull’s question was. It showed that Turnbull’s Parliamentary skills are still a work in progress, and that his frontbench lacks either the experience or forthrightness to rein him in. Turnbull was developing his questions on the fly, turning to consult with Bishop, Robb, Truss and Hockey, with Christopher Pyne leaning in to offer his two bobs’ worth. There’s a reasonable balance of governmental experience in that group, but obviously very little in the ways of effective opposition tactics.

Elsewhere at The Australian, it was crowing all round as the RBA and the Treasury’s work on improving the guarantee was held aloft as a “backflip”, “backdown” and “first big mistake”. It’s only a week since Shanahan was talking about how the crisis had brought out the best in Government. Paul Kelly made the effort to show up to Wayne Swan’s press conference with a visiting Chinese official before Question Time yesterday to attempt to catch him out, but only got in one question after the various translating and yelling by journalists was over.

The Oz also skipped the bit about how yesterday’s story that the RBA warned the Government against a blanket guarantee turned out to be wrong. Ken Henry demolished the story this morning at Estimates, going out of his way to describe the report as wrong, “unfortunate and falacious” in fact. This followed on from Glenn Stevens’s statement yesterday that the RBA supported the package.

Still, we shouldn’t let either the facts or Turnbull’s stuff-up should get in the way of a good gotcha.