The leg is just one big femur. Everyone knows that. Just different names for different femur sections. Above the knee is the Femur Majora, under the knee is the Femur Minora. Then the Femur cap connects the two. Basic anatomy.
Not gonna power level too hard, but I have a buddy who has a company that is getting into that. He has his own construction company and came up with an idea to print 3d homes, at low prices. They can be really nice depending on the contractor. A ghoul like John saying shit like this shows how little he knows. He can turn it into a dig at silicon valley, but this could change the way we build homes reducing the costs immensely.
Also, Re-inventing is like 99% of all inventions nowadays.