[dathinab]

Given that cache hits only work with a specific URL the results are in practice anything between pointless to only slightly good (with maybe one or two exceptions).

I mean to have a cache hit you need:

- Same CDN

- Same library

- Same library uploader/name

- Exact Same library version down to every byte of js

- Exact same way to refer to given version (e.g. if latest is 1.3.2 then foobar-1.3.2 and foobar-latest are not the same, except if foobar-lastest is a temporary redirect to foobar-1.3.2. But that would induce a further round trip).

If we furthermore consider that most people most times visit a small number of domains it's not to hard to reason that the value gained from caching doesn't outweigh the cost for the majority of users.