I'm terrified of stressing them out though I had one not grow past 4 inches and fully flowered.
I have one doing that this year, it's just frozen in time and even though it looks healthy, it's barely growing, even in the ground under the sun. I've been told that the first few weeks of an autos life are critical, and that one was shocked pretty hard as a baby (long story). Of course, others grown along side it were fine. Which brings me to my ultimate opinion/point on this:
I can’t seem to get over 4 ounces of an auto . What’s the trick I wanna know. I too am very impressed with autos I think they are a freak of nature and from what everyone is saying here about them and their yields makes me want to go all autos from now on!
Genetics.
I had over a dozen autos outside last year, some were huge and some were very small and all were treated similarly enough that their size differences can not be attributed to environmental factors. We had a very long cold spring last year, it impacted some and not others, that's genetics. I had three seeds from the same pack, two put out the usual 3-5oz, the third put out about 1.5lbs. Completely genetics (and one random anomaly).
Autos are still fairly new and there are a lot of genes in the pool, I think it's going to be a roll of the dice for a while. Sure, there are environmental things that we can do to give the ones with big growth genes the best opportunity to hit their potential, I'm just saying that's only half the equation, at best. In my opinion.