Economic thought, especially in macroeconomics, goes through episodic changes. These changes are very slow to occur, and historians of economic thought try to analyze what brought these changes and how they happened. The recent doctrinal changes in Eastern Europe offer in this respect a particularly interesting exercise, because everything happened very fast. In particular, you did not even have to wait for an old generation to retire or die for fundamental changes to happen.
Nikolay Nenovsky studies, from personal experience, what happened in Bulgaria. The evolution there was particularly dramatic there because the Russian Perestroyka was largely ignored by the political and intellectual class, and thus change had to happen much faster thereafter. Also, the economic transition happened in a theoretical vacuum, as only transition to communism was researched. Subsequently, economic research was largely event driven, reacting to price liberalization, restructuring of state ownership, foreign debt issues and the currency board.
Previous to reforms, economists were in two camps: those who studied socialism, and those who were to point out the ills of capitalism. The latter were much more ready to understand the transition and emerged as intellectual leaders. The first found refuge in Keynesianism and institutional economics. Bur all lacked empirical skills, and, ironically, sociologists took this over. But the big agents of change were the World Bank and the IMF, through their missions and advice, and imported western textbooks. Nowadays, western thinking has been adopted without much discussions about its fundamentals. Microeconomics is largely neo-classical, and macroeconomics mostly Keynesian. The latter is not surprising, given where Bulgaria is coming from.