The point parent was making is you can't slow the induction controller problem down because it would yield a completely different output due to the instability.

The point parent was making is you can't slow the induction controller problem down because it would yield a completely different output due to the instability. Slowing down the sort of pen and paper calculation the court ruled on does not change the result, it simply yields the same result more slowly. I still agree this is probably not a sufficient criterion for patentability though. There are plenty open loop systems that intuitively seem like they should be patentable... for example video encoding methods.