- Wrote a test script that translated `%s thing(s)` in a loop, measured performance cost, saw ~5% for letting locales handle these rules themselves, which seems reasonable.
- Measured performance cost of `idx()`, saw numbers 1-2% better by inlining. This is very micro-optimizey but I think worthwhile in `pht()` since it's used everywhere and often appears somewhere relatively high up on profiles.