[coldtea]

>Natural languages are not designed, they evolve.

But that's part of my point. I don't say irregular verbs were designed to be effective that way, but that they were evolved to be effective.

Hence the link with "language acquisition" being involved -- when regular and irregular verbs developed that wasn't a known theory some "language designer" could consciously follow. Just something innate that could develop because of a evolutionary advantage.

In fact, if someone merely designed, they'd probably go for all regular, rather than regular + irregular, as it's "cleaner".

>I often see people trying to rationalize some language features (such as arbitrary genders of nouns in many languages) as error correction or some "optimization" but I'm generally unconvinced.

Tons of language features are indeed optimizations for different things. Cold climates for example have languages with less vowels (keeping your mouth closed more).