This statement belies the power of orality and the size of built communities without literacy. It's more a question of understanding how it was done and how communities either trusted (or didn't) those who memorized the materials.

Another factor is how long one needed to remember various facts, especially if for commerce and over what spaces?

Were there stratifications of society based on the power of memory here? Compare the anthropology and archaeology with the studies by Lynne Kelly.

1. DeBoer 2001

Warren R DeBoer. 2001. ‘Of dice and women: gambling and exchange in Native North America.’ Journal of Archaeological Method and Theory 8 (3): 215–68.

Might it be possible that these women were actually gambling information relating to their "gathering" or other cultural practices? By playing games with each other and with nearby groups of people, they would have been regularly practicing their knowledge through repetition.

How might we provide evidence for this? Read the DeBoer reference for potential clues.

Gloster, J., Sellers, R. F., & Donaldson, A. I. (1982). Long distance transport of foot-and-mouth disease virus over the sea. The Veterinary Record, 110(3), 47-52. doi: 10.1136/vr.110.3.47