>not to in any way denigrate the design. its very cute an clever for simple controller applications. but it really kind of folds a few functions in the ur-instruction with reasonable interpretations that turn part of the machine into a nop.

It's not like SUBLEQ is a very simple instruction either. It has to read two memory addresses, perform arithmetic, and write the result back, on top of possibly branching.

This machine writes a fixed bit to one address, and reads one bit from another address, branching on it. Even if you break it down into micro-ops, that's two instructions. Set-bit and branch. I'd call it simpler.