One of the main purposes is to explain why the studies found in the literature have such divergent results.
For us it is a settled issue. We hope it's a settled issue for everybody.
Some of the studies use what appear to be obsolete data or data whose quality cannot be verified.
The (past) studies that reported a negative net energy assumed one should ignore co-products.
We find that ethanol can, if it is made correctly, contribute significantly to both energy and environmental goals. However, the current way of producing ethanol with corn probably only meets energy goals.
There's no good argument for just ignoring them.
They're more optimistic about the costs ... than we are.