My numbers are quite off his recommendations............... co2 is not necessary if you have good air flow in and out (negative pressure). My humidity levels are generally lower than he recommended (to reduce possible issues) and my temps are probably in his range most of the time. I'd be curious if he can hit 2.3 GPW like I did my very first grow????????
There's lots of variables though that he does not cover. My pots sit on a cement floor, keeping the roots cooler than many others. LED hanging height was not addressed. Numerous other things too, so generalities are fine bu you have to fine tune things to your situation, not someone elses.