To some degree, sedentary Amerindians were already "pre-adapted" by their earlier heritage as hunter-gatherers in temperate/sub-Arctic environments (which require planning over a yearly cycle).
It may be significant that the pace of cultural change seems to have been faster in eastern North America than in Mesoamerica, and faster still at the northern end (i.e., among the Iroquois). It looks as if advanced sedentary societies tend to arise at lower latitudes but are then overtaken by faster developing societies at higher latitudes.
This may tie in with the correlation between cranial capacity and latitude, even among Amerindians. Northern hunter-gatherers tend to evolve the highest cranial capacities because hunting distances are longer and require greater storage of spatiotemporal information. When these same hunter-gatherers become sedentary and agricultural, they have more potential for further cultural evolution.