How do we use our two brains?

I've been interested in left/right brain dynamics ever since I read The Origin of Consciousness in the Breakdown of the Bicameral Mind  in the late 80s.  Then I took a drawing class from Betty Edwards in the late 90s.  Lately I've been reading a number of other books that tell various stories about how the left and right brains interact.  They all tell different aspects of the story, and I believe I can tell a story that ties them together into a consistent narrative.  In the process we will see a fantastic (in the full meaning of the word) story about our origins as a species.  You will have to decide whether something fantastic can also be true.

The books I will try to integrate are:

• The Origin of Consciousness in the Breakdown of the Bicameral Mind (1976) by Julian Jaynes.
• Drawing on the Right Side of the Brain (1989) by Betty Edwards
• My Stroke of Insight: A Brain Scientist's Personal Journey (2006) by Jill Bolte Taylor
• Left in the Dark (2008) by Tony Wright and Graham Gynn
• The Master and His Emissary: The Divided Brain and the Making of the Western World (2009) by Iain McGilchrist

I am not especially well read, so there may be other books that bear on this subject.  Please let me know about them.  I am not academic, so the presentation may be a bit haphazard.  I am not compulsive, so there may be factual errors. 

Each of the authors of the above books has his/her own point of view, and I urge you to read the books to discover it.  I may mention their points of view in passing, but I will primarily be presenting my own point of view, not theirs.  I have no idea whether any of them will agree with my thesis.