"The results of this study are consistent with the findings of the previous evaluation of KiwiSaver. For example, Law et al. (2011) found no association between KiwiSaver membership and expected retirement income outcomes (an important element of which must be net wealth at retirement)," the report says.
"The current study, which uses completely different techniques and data to that initial evaluation, provides a second piece of evidence which suggests that KiwiSaver has not been associated with greater accumulation of net wealth by its members and hence improved retirement income outcomes."
Law and Scobie do, however, offer the standard warning to interpret with care, pointing to "evidence of significant measurement error in key variables", which they couldn't quite scrub out of the data.
But the biggest weakness of the research - that the authors also fess up to - is its brief analysis period, covering KiwiSaver only for its first three years of existence.
While the study attempts to airbrush over this failing with "regression estimates [that] suggest... tenure in KiwiSaver has little effect on net wealth accumulation", it seems more than harsh - even for statisticians - to judge the success of a long-term savings program on the strength of three-years' data.
The years since 2010 have overall provided good investment returns for KiwiSaver members, potentially adding to their net wealth above and beyond contributed amounts.
According to Financial Markets Authority reports, in the three years from March 2011 to March 2014, KiwiSaver membership increased from about 1.75 million to 2.3 million while funds under management rocketed up from $9.1 billion to $21.4 billion.
Of course, the above information doesn't really refute Law and Scobie's point that in aggregate New Zealanders might have saved this much, or more, anyway without KiwiSaver - but it does require analysis.
There's also the possibility - again I can't prove it here - that while KiwiSaver might not have improved the quantum of New Zealanders' savings it could have reduced their risk by diversifying the asset base.
KiwiSaver does need to be accountable for its core claims: studies like Law and Scobie's are invaluable in probing assumptions issued by the industry as fact.
The duo based their findings on data extracted from the 'Survey of Family, Income and Employment Dynamics' project - known as SOFIE - which ran for eight years until 2010 (hence the scope of the report).
And that's the other problem with Law and Scobie's study: there won't be another one.
