I do agree, you do want to have your grow dialed in with every thing else before the CO2, IMO. You know growing has different levels and it is a learning experience and you learn by going threw all of the steps rather than by skipping them.
Kind of like a new carpenter or mechanic, why go out and by $5000 in tools if you only no how to change the oil and air filter, or change a door knob and put up some trim.
Adieu