But that's not discounting the medieval model which heavily encouraged development because it was very unique. You not only had the external factors of kingdoms who were all relatively on the same level technology wise looking for advantages. You also had the internal factors of nobility, royalty, church, the guilds, all competing against each other for dominance.

But you are discounting 400 years of piracy and slave raids of Europe by mediteranian Muslim states that hobbled kingdoms across the continent and only ended when Christian Europe united in the Crusades.