Last night, several Adelaide executives spent the night roughing it for a good cause in the annual Vinnie’s CEO Sleepout.

As one political reporter pointed out on social media, Bank SA boss Nick Reade was the standout fundraiser, bettering his target of $162,000.

Awkwardly, that was about 16 times more than the five members comprising “Team Treasury and Finance” managed between them – although, of course, well done to them all for their efforts.

And fear not. If there’s any disparity in the respective funds, they can always just take some of the money the bank boss raises and add it to their own donation.

It would, at least, be broadly consistent with current Government policy.

And let’s face facts: the Weatherill Government’s bank levy is cynical, desperate, ad hoc and slapdash economics.

Tom Koutsantonis has evidently decided to channel his favourite politician in Jeremy Corbyn, with a budget measure rooted in class warfare and business vandalism.

It’s like getting to the till and realising your wallet is empty and then opting to mug the smug, wealthy-looking fellow behind you in the queue.

But the thing is, even though everyone else in the shop knows that what you’re doing is wrong, many of them may still feel some schadenfreude about the arrogant fop getting his comeuppance.

And therein lies the other point.

The bank tax is also savvy, and impeccably targeted identity politics.

It should be the easiest thing in the world to attack, and yet for an entire week now the main focus of political attention has been not the economically-desperate Government, but the politically-flailing Opposition.

Steven Marshall is wont to stick to his trusted refrain that all will be revealed in due course.

Of course, he’s said that before.

Before the last election, indeed, the Libs were so determined to play the policy-lite card, they actually went to polling day without revealing all their policies.

That’s right: it wasn’t that they didn’t have enough policies to announce; I’m told they actually had policies that they decided to keep in their back pocket, because they didn’t want to get sucked into having to debate their merits.

Which is fine, because of course a small-target strategy was certain to win them office, right? Oh, wait…

The Libs have shown themselves more willing to engage on policy since 2014, but the legacy of that campaign continues to haunt them. There is a lingering perception of a party – and a leader – that is vacillating, bereft of ideas.

The perception isn’t entirely fair, but it is self-inflicted.

The problem is, Marshall – quite reasonably – wants to pace himself on policy this time around. He wants to get the response right.

And sometimes the right response is a quick response.

Otherwise, you find yourself merely looking indecisive.

The vagueness of Marshall’s responses on the banking tax, and refusal to elaborate on his party’s intentions, has allowed due diligence to fester into indecision.

He has said the Libs will not be blocking the budget, but left the door wide open to amending it to remove or curtail the bank levy.

He has consistently reiterated this will be decided at the next partyroom meeting on Monday afternoon. After which it will be either dropped to a sympathetic media outlet overnight or, more appropriately, unveiled in his budget reply speech the next morning.

But it’s not a good look: it suggests one or all of the following: that the Liberal leader is incapable of taking a firm decision unilaterally; that the partyroom is unwilling to fast-track its decision-making processes when confronted with significant policy challenges; that the party as a whole doesn’t want to commit to a policy position until it’s first asked as many people as possible what the policy position should be.

Given the rhetoric, and the growing pressure that Marshall’s indecisiveness has allowed to be heaped on his shoulders, it seems likely the Liberals will seek to block the tax in the Budget Measures Bill, as it did with the car park tax three years ago – and following the Australian Conservatives’ own swift move to disallow the levy.

“It would be extraordinary for us to block this measure – but these are extraordinary times,” Marshall intriguingly said several times this week.

So, we may be agreed – the bank tax is cynical, desperate and slapdash economics.

But it should not be blocked.

Not in the interests of good government in the longer term.

We elect governments to govern, and the annual budget is part of that contract. If Oppositions and cross-benchers start cherry-picking elements of the budget they like and don’t like, before long we become ungovernable.

Businesses may not like the means by which the Government is generating its budget revenues, but businesses also need some degree of certainty about government spending commitments. If the bank tax is blocked, it would set a precedent that would allow subsequent oppositions to simply remove contentious measures from any future budget.

And if government revenues can be hijacked by the political process, there can be no certainty about government spending either.

Yes, the bank tax is a desperate measure – and arguably one whose negative repercussions will far outweigh any short-term benefit. But it is far from the most contentious revenue grab in the state’s history, and hardly worth overturning a well-established convention that the budget bill must not be held captive to the political whims of the parliament of the day.

The Opposition has already pledged to reinstate ESL remissions if elected; if they’re committed to overturning the bank tax, that too should form part of their election platform.

They don’t want that, of course.

Why would they want to go to an election having to defend the big banks, with Labor playing itself up as a political Robin Hood – stealing from the evil barons to spread their philanthropic largesse among the huddled masses?

But by seeking to cauterize a political problem, the Libs have already managed to make it worse.

Their next move could make it disastrous.

Tom Richardson is a senior reporter at InDaily.