Thanks for the reply Armin.
I will have to have a think of loop methods I am not so sensitive for 4mm, within one ~16mm loop is enough for me.
The Peak 4 sounds a very user friendly kite especially for the long term then. I have seen others would like smaller ones. I also think single skins are perfect for training or school kites because of their durability. Smaller sizes would be good for children as well, the fact they may not relaunch could be a positive in some regards for safety.
Designing for shrink is certainly interesting. I have thought on this a lot. I am certain you have followed my words too from a long time ago on foilzone there is without a doubt methods to design for this. Using differing diameters of line is one, Flysurfer has already used I know. Another is to design for what the line will eventually shrink to. Wittingly or unwittingly the prototype stage can design for this, somewhat. Here me out. Even in say a short time of a few weeks, kite bridles taken from new will shrink to something different. If you spend time with this kite adjusting, maybe lengthening some lines or shortening others, you will come to new lengths especially when measure again at 5kg or if the alteration are merely calculated against the made lengths. Well when these new lengths are made after a few weeks they will shrink to the lengths you altered for and so the kite should fly as you had hand tuned it. This I have witnessed with a few Flysurfer models now. A kite restretched does not fly quite right but after a little while does. If you were to carry the prototyping a little further maybe a year and adjust for the shrink you could account for most of it. You could highly likely come to formulas that calculate the likely amount any line on the kite would change.
I get Flysurfer has secrets and given nations like China it is the only solution for protection, but if lines are not stated as desired it can present a problem down the line. A quagmire indeed. Maybe if so it would be better to just present the desired lengths and not as made.
Awesome it is good to hear you are developing a new mixer. Flysurfer's design ethic is likely the best in the industry. To not release products before they are ready and proven, shows a great responsibility and care for your customer.
I am quite happy to discuss things in private if you want.