Exactly. Fuel is fuel. It's the incomplete combustion that is indirectly measured by the presence of free O2 in the exhaust that makes the engine computer make adjustments.
Also, bear in mind the engine PCM doesn't always desire 14:1. If you're working on a project, bear in mind that...
I'm not a chemist but I am an auto tech. My assumption would be that it would depend on the ratio you added those elements. If they were added in a stoichometric ratio then the PCM would make no further changes due to complete combustion (you would get more work out of the engine though). If...