[jibal]

> Soo evolution doesn't always optimize for biochemical efficiency in isolation.

How could it?

Evolution "optimizes" (as far as local hill climbing can go) fitness, which is the ability to produce viable offspring. Genes get mutated and then combined (in sexual species) and passed to offspring via reproduction ... that's the process that results in biological evolution, which is the change over time of the presence of alleles in a population. That's it -- there's no secret "evolution" sauce or engine. The optimization for fitness occurs through the environment affecting the relative survivability of traits--traits that increase survivability become more common in the population--this part is tautological.