John and Paula were talking tough last week.

"The dream is over," said Paula. There'd be "a kick in the pants" for those beneficiaries who needed it, said John.

No longer would New Zealand's welfare system become "a lifestyle choice", said Paula.

It didn't really matter that Paula had no idea how many "lifestyle beneficiaries" there are, because everyone knows beneficiaries are rorting the system.

Just as everyone knows teenage girls are having babies just so they can get on the DPB (and not because of a myriad of other complex reasons such as being vulnerable to social pressures to have sex way too early, or just being rebellious and careless, as Paula was when she was younger).

John and Paula don't need evidence because they've had experience with welfare - they can just tell which people aren't trying hard enough.

That's why widows and women alone over the age of 50 with no children are not to be work tested under the changes. John's mum was a widow.

But widowers, and women alone over the age of 50 who are still taking care of dependent children - and were careless enough to lose their husbands through divorce rather than death - will be brought into line.

As will those "breeding for business" never-married single mothers.

You'd think then that someone like Lindsay Mitchell, a "welfare commentator" and tireless critic of the DPB, would be celebrating.

Actually, no. The benefit changes, she blogs, "are a waste of time"; they've either been tried before (and failed) or are "a continuation of current practice dressed up as a new approach".

She points out that National introduced the same work test back in 1996, with little change in the number of DPB beneficiaries.

As for making people reapply for the dole after one year, Mitchell says 84 per cent of those on the dole don't even reach one year, and anyway, the unemployment benefit isn't the problem when it comes to inter-generational welfare dependency.

Mitchell's problem is with unwed teenage mothers who keep swelling the ranks of the DPB. She says they're the ones who find the idea of life on the DPB too seductive to pass up.

Who would choose this as a lifestyle option? Not the seventh form girls at the Auckland private school I spoke to recently. They'd never even heard of the DPB.

If there are girls for whom the lonely, harsh existence of single parenting on the DPB is attractive, and Mitchell assures us there are, then we should be looking beyond the convenient stereotypes.

How miserable does your life have to be, how limited your options, how many doors must have closed in your face before this seems like your best choice?

In his book More Than Just Race (2009), Harvard professor William Julius Wilson disputes the widely-held assumption that underpinned many of the 1996 welfare reforms in the United States: that there is "a direct causal link between the level or generosity of welfare benefits and the likelihood that a young woman would bear a child outside of marriage".

Wilson writes that there is no evidence for the claims that welfare payments provide incentives for childbearing, or discourage marriage.

With nearly half of all black families headed by a single woman, he says it's the sharp increase in black male joblessness since the 1970s that "accounts in large measure for the rise in the rate of single-parent families".

The less men earn, the evidence shows, the less likely they are to marry.

The link between falling wages and increasing rates of single parenthood is picked up by Gordon Berlin, of the non-profit poverty research organisation MDRC, who has said that these two phenomena are the main reasons for persistent poverty in the US.

"The key problem facing most poor people is that many jobs simply don't pay enough."

Berlin has observed that as inequality widened and wages for unskilled Americans plummeted in the 1970s and 80s, employment and marriage rates fell and crime rates rose.

As the number of men who could support a family above the poverty line began to decline, so too did "the professed willingness of low-income mothers and fathers to marry".

Wilson argues that while culture - individual choices and behaviour - may have played a role in the worsening state of black Americans, it's the structural inequities wrought by technological change, globalisation, and other large macroeconomic forces that have transformed the American and world labour markets which are "the most powerful forces shaping individual and family responses".

Women don't need to be dragged kicking and screaming off the DPB, they need good childcare and secure, well-paying jobs.

As Auckland University associate professor of economics Susan St John wrote last week: "New Zealand's figures show clearly that when the job conditions are favourable and unemployment is low, benefit numbers fall."

A 2002 analysis by Bob Gregory, an economics professor at the Australian National University, showed that most Australian women were constantly trying to get off welfare, but most ended up back on the benefit within a short time.

"How long do individuals succeed in staying off welfare? The answer is not very long.

"Most policy emphasis is to facilitate leaving welfare support. But it is clear that the major problem we face ... is how to keep individuals off welfare after they leave."

Lone mothers seem to continually search for new jobs or new partners but the new relationships don't last.

"The growth of female lone parents on welfare is an outcome of the inability to find a full-time job and to form a lasting relationship with a partner with a well-paying full-time job.

"Good jobs and good partners are too hard to find."