normalize_for_monomorphization could normalize recursively

[catamorphism]

A FIXME says "could do this recursively. is that worthwhile?"

[catamorphism]

(I take it that it would be worthwhile if this would enable reusing a lot more instances, as that's the point of normalizing...)

[emberian]

still relevant

[emberian]

I don't think this is backwards compatible

[graydon]

accepted for production-ready milestone

[dotdash]

I guess this can be closed given that normalize_for_monomorphization has been removed.

[graydon]

Yes.