What I see here is one more case of “paralysis by analysis”, where people would rather sit around trying to figure out how to make everything into some complex math problem, often without really taking into account some of the most basic aspects of wind energy. Yes laddermill should have somewhere near zero tether drag compared to kite-reeling. I don’t see where that requires any math to figure out. Just one more reason why I’ve been disappointed that nobody ever built a laddermill after all that fanfare. I mean, if laddermill was not a good idea, then why did we celebrate Ockels in the first place? Just to keep the name laddermill for something else? I seems to me that immediate;ly degenerating into math-land rather than just building a crappy laddermill, then a better one, then a still better one, was the first mistake. Oh sure, rather than 100 wings going in a continuous loop, let’s just use one wing - it will be easier. Meanwhile we can sit around scratching our heads doing math problems to rationalize never building that first laddermill. As I’ve said from day-one, this field is pathetic in that nobody has ever even tried some of the simplest configurations. Oh well, some people would rather sit around at their computers trying to apply various mathematical formulas than get into a shop and build things. I’ve designed, built, and sold, many wind turbines, and a few AWE experiments, including generators and airfoils, and I don’t think my math has ever gone beyond simple arithmetic and knowing a few basic facts. You quickly get to the point where all you need is for things to “look right” and they work. I say “step away from the computer”. Cleanse your brain of all that debilitating math, get creative, use your hands, and get something running. You can do all the math you want, and you will miss one thing, and your machine will fly apart. That is when you start actually figuring things out.