I don't think it requires much effort. Move code you wrote here to Bijection and remove  `allCatch.opt` from invert and boom, done. Then have Injection call Bijection, just as before, with allCatch.opt.

The benefit is that existing users get a fix for the speed issue without having to change their code. We should keep the thing working well until we delete it.

Alternatively, delete it now and bump the minor version.