Optimal Reduction. Levy, you serious?

So. Egel is a term rewriter so I ended up discussing Levy-optimal reduction. I never trusted that result.

Optimal probably involves never performing the same reduction during the lifetime of a program.

Two intuitions:

1. Likely there's a result akin to halting that deciding whether two similar reductions might occur during the lifetime of a program is undecidable.
2. Optimal sharing probably can be viewed, or stated as, as an optimal search problem thus then no optimal reduction can exist unless P=NP; i.e., optimal reduction would be optimal search would be a polynomial reduction strategy for NP problems.

Something like that. Old thoughts in the back of my mind.