> the way they have largely ignored problems in other far more influential studies that were much more flawed.

From the FT article on the matter

>Nobel Prize-winning economists have heaped praised on Mr Piketty’s work. Professor Paul Krugman of Princeton University said it was safe to say the book “will be the most important economics book of the year – and maybe of the decade”.

It is something that clearly had been billed as an influential book, even the leader of the opposition in my country commented on it.

Clearly someone felt it was worthy of review. Meanwhile, I'm not aware of any of my nations political leaders basing policy on the Tol 2009 paper. Generally such academic papers don't reach as many readers as this book has/will/wouldhave.

I think the question of one investigation being a sign of a systemic bias is a bit of a moot point.