Another opinion poll, another data point on a nice flat line. The two-party swing is stuck on about 7%, and nothing anyone does seems to be able to shift it.

Most observers now accept that next week’s result is a foregone conclusion. But they find that surprising only because Australia has had such a long run of federal elections that were not so predictable. Starting in 1987, seven elections running were regarded as too close to call right up to the last week.

Prior to that, however, we had five elections – 1975 to 1984 – where there was no such doubt. So there’s nothing particularly unusual about an election that lacks the excitement of an uncertain result. We’ve had plenty of them at state level as well: 1992, 1996, 2002 and 2006 in Victoria; 1999, 2003 and 2007 in New South Wales; and many more.

Such elections can still be exciting, and throw up unexpected features. For example, the swing against the Hawke government in 1984 came as a surprise to almost everyone. The size of the 1975 and 1977 landslides also came as a revelation to many, as did some of the recent Labor state victories.

And regardless of the size of the swing, there will always be some interesting individual results. Some apparently safe seats will be lost, while other vulnerable MPs will hold on. Indeed, a landslide is more likely to be interesting at electorate level, since more seats are in play: it shouldn’t be necessary to drum up artificial interest by pretending that the overall outcome is in doubt.

Conversely, one of the “too close to call” elections – 1996 – actually turned out to be a landslide. But many commentators (including me) had taken the wrong moral from the 1993 result and still gave Labor a chance of victory even when the evidence of the polls, although less unequivocal than now, pointed very strongly the other way.

Although some are still hedging their bets, most of them this year seem to have learned that particular lesson. But it’s taken months of historically immovable poll results to wean them from the “too close to call” mantra.

Part of this reluctance is just a cynical desire to sell newspapers or advertising time. But there’s also a genuine lack of historical memory that makes people think predictable results are something outside the norm. Not so.