In a recent working paper, former chief economic adviser in the ministry of finance Arvind Subramanian made the dramatic claim that the real gross domestic product (GDP) in India grew at a rate between 3.5% and 5.5% during 2011-12 to 2016-17.A number of critiques exposing myriad flaws of the paper have already appeared. They notably include contributions by Swaminathan Aiyar, Surjit Bhalla, Bibek Debroy , Charan Singh, and the Prime Minister’s Economic Advisory Council (PMEAC).Subramanian’s analysis is so problem-ridden, and its claim so far-fetched, that there are only two possible explanations for why he wrote it. One, he blundered — he simply did not realise the innumerable methodological problems afflicting his analysis. Two, he was aware of the shortcomings, but chose to ignore them in the hope of creating a sensation and gaining the attention of the government, media and, possibly, the whole world.If Subramanian were a young scholar, fresh out of graduate school, one could imagine that poor understanding of technical and methodological issues and eagerness to make a name led him to act in haste. But he is a seasoned economist.It is inconceivable that he was unaware of the numerous methodological shortcomings that are common knowledge among economists.To point out just one such flaw, I may note that his analysis assumes that a 1% growth in exports impacts GDP growth by the same magnitude in every single country during all years included in the analysis.Given that such impact can vary over time, even within the same country, this is a heroic assumption. For example, the contribution of 1% growth in exports to GDP in a country would, in general, be different when it is a nearly closed economy than when it is a highly open one.The paper has impressed some commentators because it has been circulated as a faculty working paper of the Center for International Development at Harvard University. But inclusion of a paper in the series does not mean its approval by the faculty. Far from it.Any faculty member ranging from a short-term visiting lecturer to a tenured full professor can circulate her ongoing work in such a series. A paper undergoes serious review only when submitted to a peer-reviewed journal. The paper also seeks legitimacy by referring to ‘consultations’ with a few distinguished professors at Harvard University in a footnote.That, too, means little because consultation is not the same as approval. Indeed, I will be astonished if any of the senior Harvard professors, listed in the footnote, would approve of the author’s method of producing the estimate of GDP growth of a country using cross-country regressions.Subramanian is not the first economist who has written critically of the government after serving it in a senior position. But he is the first to write in such sensational terms, and that too so soon after leaving government. That makes all the difference. Many, especially outside India, are bound to think that he is speaking on the basis of inside information and must be right. That could seriously undermine investor confidence abroad, at least until the ongoing debate clears the fog created by the paper.If Subramanian had done the hard work of studying the 40-page document by the Central Statistical Office ( CSO ) describing in detail the methodology it deploys to estimate GDP, pinpointed the flaws in it, and explained how those flaws lead to overestimation of both GDP and its rate of growth, he would have done a great service to the country.Such constructive criticism would have also served him well. But by claiming that his growth estimate, derived from a cross-country regression with four explanatory variables, is superior, he has made mockery of the painstaking work that CSO staff do day in and day out.The fallout from the paper does not stop there. By insisting that during the last two years of the UPA administration and first three years of the NDA administration, the economy performed no better than during the lost decades of 1950-80, Subramanian has also cast aspersion on the hard work of all his former colleagues in the ministry of finance.One wonders how former finance minister Arun Jaitley , whom Subramanian has fondly described as the ‘dream boss’ on multiple occasions, and Jaitley’s predecessor P Chidambaram, who adores Subramanian as an outstanding economist, both feel after being handed a failing grade by him.The final casualty of the paper has been younger outside talent whose induction into service will now be seen with great suspicion by the government. Stung by this experience, the government would now think twice before inviting another outside economist, no matter how talented. Therein lies an important lesson of this sordid, still unfolding, episode.Talented outsiders who serve the government have a difficult balancing act to follow, especially in the immediate aftermath of their departure. While they try to preserve their own integrity by offering critical evaluations of government policies and performance, their unwarranted, sensational criticisms risk throwing obstacles in the path of those who wish to follow them in the footsteps.