The study I quoted (which is the most balanced and rational and least propagandized I've come across), calculates the energy product ratio for co-products such as gluten meal based on the energy input that would otherwise be required to produce those products in a process that does not also produce ethanol. This makes a lot more sense than other methods that simply rely on weight, food caloric content (which is not directly comparable to fuel caloric content), or market value (commodity prices change).
As such, the co-products account for consuming about 20% of the input energy. This is a conservative evaluation, but it still yields a net energy balance for Ethanol of about 1.24 or 1.25. That is a positive net energy balance, but it is not nerly as positive as the net energy balance for other farmed fuels.
You'll have to expalin to me how gluten or DDG's can be produced without producing ethanol.