I have to agree with UB here. There's a lot of thing that influence growth, and a lot of things that inhibit. I like new school growing as well, but I'm not going to try can debate the fact MJ has been grown for longer than I've been alive While topping and pruning techniques do have their place, its most only beneficial in an indoor environment, and I'm almost positive if you compared the results side by side it wouldn't be that much difference. Plants are somewhat limited in their capability, and even if you managed a technique to "encourage" more growth, it would require more nutrients to be possible. So in essence it's not quite doubling the yield, but upping the possibility.
Now, that doesn't mean the technique isn't beneficial, especially indoor. Under a limited or unidirectional light source (unlike the sun that moves) an even canopy means more than having "more" foilage. Who's really to say that all of that foilage is getting hit by light, thus undergoing intense photosynthesis, that would impact growth.... compared to limited photosynthesis which is good for sustainability. No different than seedling with no leaves and slow growth, or an LST or SCROG with crazy growth.
I do honestly see desertrats method as having substantial weight and reason. Am I willing to try it? No, Not quite yet. Mainly because I believe while it works it would come at a sacrifice of veg time. Is that wrong? Absolutely not. It's just not the way I'm used to, or like to grow.