Wishful thinking and laziness comes to mind. I have read well thought out critiques of corn ethanol then have the author tout sugar cane ethanol with little or no inquiry into costs.

What do you mean about costs from sugar cane ethanol? Up until recently the majority of ethanol produced was from sugar cane, and most of that without significant subsidies. It seems odd to suggest that cost is an issue that needs a lot of thought when there is a large existing market for the product.