However, I wonder if this isn't treating a symptom versus a root cause.
Is saving that 5s round-trip so common in your workflow that you needed to optimize it, and would it be more productive to refactor the app so you and collaborators are working on different files?
Also, this has the entirely valuable guidance that pushing to a local server is much faster than a remote server. There's a Github Enterprise product, for you to run close to you. It'd be an interesting calculation to see the performance hit from waiting 5s to push to a remote server, versus the performance hit from keeping your nearby server up and patched.
But nice to read, kudos all the same!