I haven't read the thinking course book, but I have read a good deal of his Serious Creativity. I was impressed by what I read.

I think the problem is that lateral thinkers (such as the good doctor) make statements which are obvious in retrospect. His critics probably wouldn't get the solution to the, "Can you make an egg stand on end on a flat surface?" puzzle, but would pat themselves on the back for giving the correct answer to, "Will an egg stand up if you break it in order to flatten one end?"

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If you could touch the alien sands, and hear the cry of strange birds, and watch them wheel in another sky, would that satisfy you?