Are authoritarian regimes better at promoting economic growth?

I few days ago, I asked whether Rwanda should follow in Singapore's steps and clamp down on civil liberties in the interest of economic development. In the back of my brain, something was telling me that I had read Kagame's theories about development somewhere before.

Now I remember. The late great Samuel Huntington (of Clash of Civilizations fame), in his book Political Order in Changing Societies, argued that societies go through upheaval during modernization because popular mobilization outpaces the development of political institutions. Huntington fetishized these institutions, in particular political parties and argued that in poor countries it would often be easier for authoritarian regimes to develop these institutions. I am reducing a 500 page book to a paragraph, but bear with me. Huntington, a Harvard professor, later went on to provide advice to the military junta in Brazil, recommending they develop a strong party system before liberalizing the political sphere.

Of course, this elicited a lot of criticism. More recently, Adam Przeworski - an established Polish political scientist who knows something about authoritarian regimes - put Huntington's theory to the test. He examined 135 countries between 1950 and 1990 and did the necessary econometrics to figure out whether authoritarian states were better at developing than democracies. His conclusion:

Indeed, the 56 dictatorships with annual per-capita income of less than $1,000 when we first observed them simply failed to develop. By the exit year, only 18 of them had made it (whether under democracy or continued dictatorship) to $1,000, only 6 to $2,000, and only 3 to more than $3,000. South Korea and Taiwan are exceptional: they are the only two dictatorships that started under $1,000 in 1950 and had annual per-capita income exceeding $5,000 by 1990. If we consider as "initially poor" those countries with less than $2,000, we find that among 98 dictatorships first observed below this level, by the exit year only 26 had made it to $2,000, 15 to $3,000, 7 to $4,000, and 4 to $5,000. These figures should be enough to dispel any notion that dictatorship somehow promotes economic growth in poor countries.