I don't really have a horse in that race... it seems like a reasonable idea, but I don't think we're anywhere close to having the tools to confirm/deny it, or even to just observe what's going on with enough fidelity to make a guess.

My view of neuroscience is that we're decently good at figuring stuff out at the very very low level (e.g. behavior of complex molecules, classification of cell types and basic low level functions), and at the very high level (e.g. "this region is responsible for speech"), but haven't really made the right breakthroughs for figuring out the mid level (e.g. "how exactly does this ball of 50 million neurons perform its function, architecturally"). This theory seems to lie in that middle area.