This may be just my ignorance ... but couldn't reflection be tweaked to work with both stran based and trans-mapped hair?  I'm sure it isn't the most accurate ... but couldn't it be more useful than anistropic?

Strand-based hair is not a 3D object at all - it's a collection of tiny 2D billboards, rotated so they always face the camera. They're not round. They don't reflect correctly no matter what you do. As for reflection on transmapped hair - it can look decent, but takes ages (literally days) to render.

---

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)