Two weeks of Senate Estimates kicked off this morning with Communications, the Parliamentary Departments, Attorney-General’s and Agriculture first up.

The big portfolios — Health, Education, Families, Defence — and Treasury come next week.

In the aftermath of the budget, this should be a target-rich environment for Opposition senators. There are savings to be investigated. There’s the National Broadband Network proposal to pull apart. There are Treasury’s economic forecasts to discuss. There’s Defence’s investigation of the Helen Liu business. Private health insurance issues to tease out. Mick Keelty’s farewell appearance should involve some grilling over the bikie brawl at KSA. If the Opposition can’t score some points with all that, it should give up.

So far, however, the Coalition has botched the Estimates process, frequently preferring indignant ranting and abuse of bureaucrats over the sort of forensic probing that yields results and headlines. Sometimes senators haven’t even shown up to question agencies they’ve called to appear.

Treasury appears next Tuesday, the day of the Reserve Bank board meeting, which means Ken Henry won’t be attending. But the Economics Committee has graciously allowed three whole days for Treasury and its agencies, meaning Dr Henry may not escape unscathed. The roll-up of Coalition senators at that hearing will be interesting. Previously the Coalition has, either through bad judgement or indiscipline, sent swarms of senators in to grill Treasury, signalling just how badly they wanted to score points off Henry.

This not only created the impression of an inquisition — or in fact something closer to King Kong Ken versus the biplanes — but also meant the Coalition’s attack was all over the shop. Eric Abetz would be building up a bit of momentum trying to pin down Treasury on the chronology of its advice to the Government, and the economically-illiterate Barnaby Joyce would interrupt to ask for an explanation of the simplest of economic issues. At one stage last February, Henry actually wondered aloud if the committee wanted to go off on such a tangent mid-grilling.

Today also marks the start of two weeks of House of Representatives sittings. There will be a week’s break at the long weekend, then another two weeks. It will be the most intense period of Parliamentary activity all year, especially with Budget bills and the Government’s emissions trading scheme bill being considered. It will also be a key period tactically. The Government will be looking to re-establish the dominance of its political messaging that it enjoyed until the Budget. Hitherto disciplined and ruthless, it got too clever by half over the Budget, first sending a confused message, then engaging in the most blatant and hilarious spinning over the actual deficit numbers.

That was a small but important victory for Malcolm Turnbull. His emphasis on debt and deficit threw Rudd and Swan. A Government that is normally smart and focussed looked rattled. Expect the Government to respond by shifting the debate back to its preferred territory of nation-building and climate change over the coming weeks. Parliament will enable impact players Lindsay Tanner and Julia Gillard to take some of the load off Rudd and Swan. Chris Bowen won’t mind jogging to the dispatch box to handle questions about employee share schemes either. The Government will look to affirm the dominance in Parliament it has enjoyed this year over an Opposition which, Joel Fitzgibbon’s SAS pay troubles aside, has been listless and uncoordinated in Question Time.

As both Turnbull’s success on the deficit and the rapid cave-in on employee share schemes shows, this is a Government that is easily spooked. Its vulnerability is its popularity, which it seems to prize above good policy. A more disciplined and patient Opposition might be able to exploit that, but we’re still waiting for one of those. Phil Coorey’s cracking yarn today on internal Liberal divisions and conservative tactics aimed at overturning shadow Cabinet decisions shows the Coalition is never more than a brain explosion away from another bout of in-fighting.

And on that score, the ETS bill has the capacity to play merry hell with Malcolm Turnbull’s plans.