Sacrifice stabilized Maya?

Weinberg:  Mel Gibson's heart of darknessWar was a choreographed and symbolic affair for the Maya, more to do with establishing the hierarchy of city-states according to agreed-upon rules than with territorial conquest. War was determined by a calendric system based on the movements of the stars, so the surprise attack Gibson portrays was virtually impossible. And in contrast to Gibson's portrayal, villages were not put to the torch, lands were not ravaged. Nor were peasants (much less largely non-existent hunter-gatherers) the victims. The point was ritual degradation of the kings and high-ranking warriors of the vanquished city-state. It was not the mere arbitrary sadism of “Apocalypto.”

Indeed, one theory on the still-mysterious demise of Classic Maya holds that the abandoning of this system of ritual warfare in favor of fight-to-the-death campaigns of territorial conquest (possibly due to the influence of central Mexican peoples who began to penetrate the Peten) upset the political balance in the rainforest. So, counterintuitively, the system of human sacrifice seems to have had a stabilizing and sustaining effect, channeling aggressive tendencies into controlled ritual form; it was the erosion of this system which may have precipitated the collapse.