My issue with the social progress through economic development strategy is that it really depends what the issues were that the smallfolk were dealing with: if the major issue of the day was famines and high prices, large numbers of landless younger sons, etc. than pushing economic development is a good idea. But if the issue is the nobility rampaging over the peasantry, pursuing a strategy of “let’s wait a few generations for the merchant classes to rise before doing anything about it” doesn’t seem great.