Idk if this will help and it sounds like a pain in the butt, but.... I was reading an article by sub cool a while back and he was talking about the science behind cloning and mentioned something about air layering and wrapping the stem in advance to promote the white tissue (he uses scientific terms, I say white tissue) that sprouts the roots. I see this white tissue when I use my coco method, which by the way has already started rooting.... So basically you would wrap the stem with some sort of tape to block the light and air a week or so before taking the cut, and it would make changes to the plant tissue making it root much faster. I have seen this effect when I super crop, I just break the whole stem and tape it with duct tape, when I peel it back a week later, the tissue is white and looks just like the transition phase I was mentioning, where it turns white and swells up just before the roots pop out.