Dude...you obviously haven't been doing as much reading as you could be doing to answer your own questions.

Yield depends on many different things.

â?˘Soil, water, aero environment
â?˘CO2?
â?˘Fertilizer / Nutes
â?˘Light cycle without any light leaks during dark sections
â?˘Watering Schedule
â?˘Watt / sq.foot
â?˘Not to mention the most obvious one, whether or not the genetics of the plant tend to produce more or less bud than average

There you go, Whenever people ask about how much yield they can expect I always laugh cause there's no way you can estimate really...