In this blog, we take a look at modelling used to justify ‘endgame’ legislation under discussion in New Zealand. Among other things, this would reduce nicotine in cigarettes and other tobacco available through legal channels to minimal levels. We find the modelling and data assumptions bear no relation whatsoever to the underlying processes and the effects that such legislation would trigger. Deep cuts in smoking are assumed as inputs to the model. Unsurprisingly, therefore, the model results show deep cuts in smoking, and this determines the resulting health benefits. But the assumptions have no grounding in reality and misinterpret and misuse trial findings.