They have probably been doing it this way since long before 1900. From what I've seen, Burr doesn't seem to be a problem and shouldn't if the spacing is correct. My version will be substantially larger, no super for now, thinking if the top hinged back as well frames could be tipped out, maybe put frames on drawer guides to slide out, maybe hinge frames themselves to be opened like book, think Huber did this ? Possibilities are endless as is my imagination. An AZ/Perone hybrid. Like America, I take the best from any and everywhere and make it my own :) I think these Slovenians have come up with a pretty impressive system, not well known probably because Slovenia isn't. Thankx for the internet.