When governments make unpalatable changes, it's always best to do so straight-up. But that doesn't come easy to politicians. You never hear the Prime Minister talk about "asset sales"; he always refers to "the mixed-ownership model".
Education Minister Hekia Parata's pre-Budget press release that sparked the furore about bigger classes was headed, "Focus on quality will raise achievement". It was not until almost half-way through the release that mention was made of "some changes to funding ratios". The word "quality" appeared five times; the word "cut" not at all. It was, in short, a study in spin.
In the staffrooms of the country, no one was fooled. It quickly emerged that "funding ratio changes" meant the loss of teachers of specialist subjects, particularly technical. One Auckland school said it might lose up to 10 teachers.
Parata's numbers made it plain that, unwilling though she was to use the term, this was a cut.
"In years 2-10," the statement said, "the funding ratio will standardise to 1:27.5 from the existing range of 1:23 to 1:29." The class dunce knows the mid-point of 23 and 29 is 26, below the standardised 27.5.
Quite properly, much of the ensuing focus has been on the embarrassing political mess caused by a policy announcement based on numbers that had not been adequately crunched. John Key was forced to concede that "there were some hard edges for a small number of schools". But at least as problematic was the thinking underlying the change.
Ideologically, the Government is much enamoured of the research of Professor John Hattie, whose 2009 analysis of 50,000 studies of 83 million students concluded, among many other things, that class size had little effect on learning.
That research inspires the Treasury's chief executive, Gabriel Makhlouf who, since his appointment a year ago, has made it plain that he considers education his business. (His February briefing paper to Finance Minister Bill English, which suggested that improving teacher quality could be funded by increasing student/teacher ratios, was the basis of this week's announcements).
But the simplification of Hattie's findings about class size is disturbing. If they are taken in isolation, the logical outcome is classes of 1000. But Hattie also found that what boosts student achievement is how teachers engage with pupils, and how much detailed feedback they receive about their progress. Such matters are, obviously, profoundly influenced by class size. In short, Hattie showed that class size was not, in and of itself, a predictor of achievement; he did not say it was irrelevant.
The pretext for the ratio changes is that they will free up money to "raise achievement [by improving] teaching quality," as the minister put it. But any educationist will tell you that "quality teaching" is a deeply problematic term because no one agrees on what it means. As a US Supreme Court judge famously said of pornography, it's hard to define "but I know it when I see it".
We all remember our "good" teachers (though, tellingly, we don't necessarily all agree on who they were). But how might their "quality teaching" be numerically quantified? The national standards regime, introduced by Parata's feckless predecessor Anne Tolley, will reflect nothing so precisely as the socio-economic status of the communities they draw on; and no one would argue that there are no good teachers in under-performing schools, or bad teachers in top schools.
The fact is that the present moves will make it harder for teachers to deliver quality - and disproportionately harder for teachers in low-decile schools whose pupils are attracted to the subject areas under attack.
If the Government were to present the initiative honestly, as cost-cutting, that unfairness would be plain. Instead, it presents it as a commitment to a nebulous notion of quality, which is really so much political humbug.