I'm seeing the same thing with my own little app that implements several new heuristics for functionality and optimisation over a classic algorithm in this domain. I came up with the improvements by implementing the older algorithm and just... being a human and spending time with the problem.

The improvements become evident from the nature of the problem in the physical world. I can see why a purely text-based intelligence could not have derived them from the specs, and I haven't been able to coax them out of LLMs with any amount of prodding and persuasion. They reason about the problem in some abstract space detached from reality; they're brilliant savants in that sense, but you can't teach a blind person what the colour red feels like to see.