I suspect your production theory is spot on.
A 19th century, streamlined process hellbent on maximizing profit and humpa-reproduct-ability. I'd buy one just to rip it apart, but they sell for way to much money. Every time there's a fake flip auction on eBay, some knucklehead snipes it out from under me for hundreds of dollars forcing me to buy a real one for less. Very disappointing.
If only I could get my hands on one. I could take it a apart to analyze the materials and mauncfacturing techniques. Then, I could use only the highest quality materials, highly paid/skilled workers and vastly improve on current humping techniques. I've found numerous WW2 factory workers itching to get back to work.
My goal is to make an ultra high quality humped flip and charge double what a real one is worth. Only in this way can we, the collector community, convince others to learn how to identify and thusly buy real ones. Adding a turbo or supercharger might help.
Meh, it's probably easier to just start collecting marbles.