… argument for this caching to be a core piece of ASDF … ?

My apologies, I should have known that saying “proof of concept” wasn’t
sufficient to signal that - yeah! , it’s a vile hack not ready to be integrated
into anything, including my own day to day usage.

In fact I put forward code because that’s how I test that my ideas have any
grounding in reality.

Good point about how people are likely to be switching configs, not one of
they many open issues I’d already noticed.