The assertion:
'To say that myths express truth, perhaps in a way that nothing else can, is basically a sales pitch by religious people to persuade doubters to stay in the faith.'

is, in my humble opinion, shortsighted. I would not consider myself a religious person by any means, but I would say that I am spiritual. My faith in Christianity unraveled when I was in High School, but once I started reading Campbell, among others, I began to see WHY it did. The debate between blind faith, and reasoned dissent is an important one, but as was mentioned in the article, they are both capable of missing the point.

Campbell wrote in "Thou Art That" that he was asked onto a radio show to discuss myth and metaphor, and when he asked the DJ for an example of a metaphor, the DJ replied, "My friend John is very fast, therefore, john is like a deer." Campbell countered that that wasn't the metaphor, the metaphor was "John is a deer". The DJ said that that was a lie, and therein lies the problem.

as was asserted above, myths cannot be concretized if they are to retain their power. Campbell talks about them being "transparent to transcendence", that when they are working properly, they point towards (or, seen through them are) truths that cannot otherwise be put properly into language. Language is otherwise too static to express these ideas. It is the "mysterium tremendum et fascinas" of existence. I have absolute faith in science to describe our world and everything in it, but it cannot hope to adequately express the raw primal experience of what it feels like to be ALIVE. It too, in a sense, is a type of mythology. Because it gives coherence and form to the world. One can stand in awe in a gothic cathedral, when reading a myth from the orient, when faced with the grandeur of a supernova, or when unraveling the complexities of a DNA helix, but through them all runs the same thing.