> After you read it, you'll understand that the "policy debates" the masses are exposed to have very little resemblence with what preoccupies decisionmakers! The government, no matter the administration, is far more rigorous and strategic than people give it credit for.
In this case the example document you quote is rather poorly chosen and does not really seem "rigorous" at all. Most if not all topics the document touches are basically the same that monopolize "policy debates" everywhere all 24h of the day (immigration, nationalism, welfare, and immigration. did I say immigration?), and the conclusions are defended as poorly as your average comment from Reddit. The document does not even get the names of many regions and cities correctly; the grammar is at many points terrible; many of the figures and charts look as if made with Paint, and whenever they are not, they are screen-scrapped from random websites and then poorly JPEG recompressed. Heck, at some point they even use Google Trends as source...
My humble opinion about these "think tank" reports that get "leaked" is that they use "commissioned by X government" just to advertise themselves, and it's either false or meaningless. I'm quite sure that the "serious" government analysis, if they exist, don't get leaked since that would probably immediately ruin all the predictions.