They are. The times I've been caught were clearly my mistake. Those times and various close calls have been cases of almost symmetry. I've also done things like

They are. The times I've been caught were clearly my mistake. Those times and various close calls have been cases of almost symmetry. I've also done things like building two identical units in series or parallel and watched myself learn. I can imagine a great speed up with practice. An apartment's worth of furniture could take me a day, and I can well imagine paying someone $100 for an hour instead.