> ... but not in a specially useful way ...
It can be very useful: https://github.com/google/crfs#introducing-stargz
It can be very useful: https://github.com/google/crfs#introducing-stargz
It could be a typo, though I think when we say something "isn't specially/specifically/particularly useful" we mean "compared to the set of all features, specifically this subset feature is not that useful" not that the feature isn't useful for specific things