The legislation for the carbon pricing package is indeed “by far the most important vote that the Australian parliament will take in the current term of parliament”, as Tony Abbott said last week. And yet the Coalition trooped out, nearly as one, when the Prime Minister rose to introduce the bills yesterday in the House of Representatives. Evidently not quite as important as all that.

The government showed up the opposition’s inconsistency by congregating in the chamber to hear Abbott lash the bills this morning.

The opposition insists there’s not enough time to debate the massive set of bills; the government points out it’s considerably longer than the Parliament had for the WorkChoices legislation. No one mentioned the Howard government’s NT intervention legislation, at 500+pp, that was rushed through so quickly in 2007 that even Liberal MPs had no idea what they were voting for.

But in the usual way of “do as I say, not as I do”, the opposition walking out on the Prime Minister is a more appropriate demonstration of the importance of Parliamentary debate than their rhetoric about the importance of the issue.

Parliamentary debates are rarely enlightening. Most speakers on the government side will recite speeches crafted from the same sets of talking points handed around by the portfolio minister’s office, except those who have long exposure to an issue and who actually know what they’re talking about (for a nice example, read the thoughts of up-and-coming backbencher Malcolm Turnbull on media policy in 2005). Opposition MPs rise to rail at the government and declare they’ll oppose whatever is before the chamber or, if they’re supporting a bill, rise to rail at the government and then declare “nonetheless, we support the bill.”

In any event, the collection of speeches given to a chamber almost entirely devoid of life plays no role in improving legislation. That happens in committees, or at least is supposed to happen in committees, particularly when external stakeholders get the chance to point out problems with a bill. Even then, governments will ignore efforts to fix legislation. The most egregious example of this in recent years was the Howard government’s five-star stuff-up of the Australian Military Court, which the High Court ruled unconstitutional in 2009, exactly as several prominent advisers such as the Judge Advocate-General and shadow Attorney-General Robert McClelland and the government’s own backbenchers, including George Brandis, had warned.

Then again, when you have control of the Senate, you tend to regard the recommendations of Senate committees with what the Prime Minister might describe as a jaundiced eye.

So if parliamentary debates are so important, what exactly do we get from them, apart from volumes and volumes of Hansard? Has an MP ever talked an opponent into changing their vote? Have wise heads within the bureaucracy, ensconced in those hideously uncomfortable advisers’ boxes at the front of the chamber, ever found themselves nodding in agreement with the points made by a crossbencher and proposed that a bill be amended to pick up the excellent point they’d made? No, certainly not in the past couple of decades.

Like question time, the dominance of the executive branch has rendered most debate in Parliament pointless. It’s only when an MP decides to cross the floor that their contribution to debate takes on any significance. So don’t blame the opposition for walking out on the climate debate. By going back to their offices to work, they were probably being far more productive than they otherwise would be.