Well, those right-handed people who have had strokes in their left middle cerebral artery distribution might beg to differ on this point. However, I got this far because I found your first paragraph to be quite compelling writing.
A stroke on the nondominant side in the same distribution leads to contra lateral hemineglect of the world. Watch these people try to draw a clock: they'll put all 12 numbers on the right side. It is interesting, to me, that the pathways are such that there is this partitioning of deficits.
It's not "left logic right creativity", but neither is it one homogenous mix.
Anyway, I think it's relevant and not simply pedantic. If you disagree, well, I suppose we can disagree politely.