1. If a novel is intended to be realistic fiction, it should reflect reality, not the author's philosophical agenda. (My opinion, but I think this is the only way serious art reveals truth. Imagine if Marx had written a novel.) This is distinct from fantasy. I'm a Tolkien fan too, but I don't think anyone would turn to LOTR for economic guidance.

2. Artificially low interest rates reflect Greenspan's belief that given enough liquidity, markets will be self correcting. He thought banks were in the best position to protect themselves from risk because they bear the greatest consequences of failure. (He has since admitted the failure of this belief.) Clearly they were not, as the low interest rates lead to further inflation of the credit bubble.