Probably not beneficial to make CO2 unless you have your plants in an air tight container; I think CO2 is pretty much apart of our atmosphere. I know what you are thinking, CO2 means more photosynthesis, but I don't think that the presents of CO2 actually induces a plant to even want to over-clock its self. It would need a lot of light with the right mixture of heat, humidity, and nutrients to go in rapid mode and I still don't find this to be scientifically proven to be sufficient. I think in most cases patience is a virtue.