The "Great Divergence"

I'm reading the Cambridge Economic History of Modern Europe, which was published in 2010 and represents a digestion of the state-of-the-art in mainstream economic history--which is to say, cliometrics and institutionalism. The final chapter is about the so-called "Great Divergence" between Asia and Europe, and the authors discuss the various positions on the relative levels of economic development of India, China, and the European countries, ultimately coming down against Pomeranz who wants to claim that the most advanced regions in China were comparable to England in the 18th century. They then go on to suggest explanations of the gap.

This is the conclusion of the chapter:

The survey presented in this chapter takes us closer to the traditional position on comparative living standards across Eurasia than to the revisionists. The evidence we have seen indicates that differences in living standards between Asia and northwest Europe had already emerged in the early modern era, and only widened further with the onset of the Industrial Revolution. The advanced parts of Asia – India and China – looked more similar to the backward parts of Europe than to the more advanced northwest. The Great Divergence was well under way in the seventeenth century.

What strikes me strange is that they focus overwhelmingly on the first part (the quantitative divergence between "northwest Europe" and Asia, which is the "Great Divergence" that "was well under way in the seventeenth century") at the expense of the second (the similarity between Asia and "the backwards part of Europe"). Together, however, these two points suggest that the real divergence wasn't so much between Europe and Asia in the 18th century as it was between England and Holland on the one hand (and the latter even falls back a little in early 19th c) and everywhere else on the other, which included both the rest of Europe as well as the major Asian economies. Central Europe diverges from Asia only in the 19th c--i.e. when it is reached by industrialization.

What I think this means is that the (NW) Europe-Asia comparison is a bit of a red herring. The question is what happened in Holland and England before the 18th c, which led to the divergent pattern that is already visible by that century. If we're going to do comparative analysis to try to capture and explain this divergence, shouldn't the first step be to look at the most immediate contrasting cases, namely France and the German principalities, and the Hapsburg Low Countries? That way, political, cultural, even technological, geographical and climactic factors are held relatively constant, as opposed to comparisons between England and China or India or Japan in which those factors are all vastly different.

After that, it would make sense to ask, first, whether what caused the gap to open up between, say, England and France through the mid-19th c also led to a divergence between England and, say, China. Then, second, whether the process by which France (and Germany, etc.) began to close that gap in the 19th c was similar or different to the way that Japan was able to begin to close that gap as well at the end of the century, and what it was that blocked that process from occurring in China and India until the latter half of the 20th c. Indeed, when the question is asked in this way, the role of imperialism seems much more important, in contrast to the authors' position, which is that it can't really explain the appearance of divergence already in the 18th c.