That's as long as the shared library is changing about as frequently as your custom code. If you're using the same framework-x.y.z library for months at a time

That's as long as the shared library is changing about as frequently as your custom code. If you're using the same framework-x.y.z library for months at a time, but doing daily/weekly code changes and pushes, you're losing out on the cachability of the library. But if your project is only being updated as frequently as the third party libraries it uses, maybe it makes sense.