Good to know this. Overkill lighting is good for me because I'm learning so I can use all the light I can get. I have noticed experienced guys getting nice grows out of minimal lighting but I'm not there at all yet. Knowing my lights are good or more than good then I can focus on other aspects of growing. There is a lot to know for sure.
And I figure the more plants I have growing right now and learn from the better. The cycles take a while so I was hoping to stagger 2 plants at a time a few weeks apart and have capacity for 6 instead of 4 gives me more opportunity to learn.
Hear you on the real question, but I can't wrap my head around that right now. For me it's number of plants.