[ironchef]

Is it a myth though? I would rather suggest studies are simply inconclusive. There have been studies outside of humans which show lateralization exists as an evolutionary tool. There have also been some in humans ("Sources of mathematical thinking: behavioral and brain-imaging evidence" in Science for example) which shows that they exist in dominant-passive manners, but not in the "all or nothing" marketing drivel that gets sold. Am I missing something scientifically or is the "myth" you're getting at simply the oversold notion of what it means in popular society?