I guess this is probably the best way to study the idea but I'm not sure how well you can map the results out long term from this study. This group of Chimps have evolved towards a tree dwelling environment and happen to be living near some plains but they're still starting from a tree dwelling specialized body. The human chimp common ancestor was less specialized, and perhaps would have acted in the predicted manner.

If we took this study to the logical extreme then chimps in the forest should be walking around bipedally in the trees, which they aren't.