Whenever there is an argument of a CLI being suboptimal you can be sure that the counter is going to be "but it's all in my muscle memory!". CLI itself isn't efficient, it just FEELS efficient. Its real strength is the scriptability, such that repeating tasks can be substituted. If you deny yourself that power, you'd probably be better off with a GUI and good use of hotkeys.
Now, I'm aware that there are different usage scenarios. A typical developer only ever works on a handful of systems at the same time period - which makes handling your personal set of scripts a viable option. Administrators are an entirely different beast.
I'd say that administrators who can't set up a system that allows them to have individual setups maybe should pick another job. Even if you're sharing a root account, you could still source your unique shortcuts and aliases. The only thing prevent you from doing that is privileges, of course (although even then there are partial workarounds).
But there is a point about optimizing typing. If you're just going to replace "git" with "g", you'll save two characters. You're probably not quite down to a third of the time, but there will be a measurable difference. But given that there's some overlap with other actions (e.g. you might already be pondering your commit message), the measured productivity increase will probably be pretty small.
In cases like that, it's probably better to look at the whole workflow, so you're not just saving time at the micro level. Save/unify several steps of the whole procedure (e.g. combine save-commit in your text editor).
And then consider that by reading this thread, you've spent x minutes that you'd have to work very hard to get back by saving keystrokes ;)
CLI is itself efficient in the sense that you're not lifting your hands from the keyboard to manipulate the mouse. Beyond that - scripting makes it more efficient.
Now, I'm aware that there are different usage scenarios. A typical developer only ever works on a handful of systems at the same time period - which makes handling your personal set of scripts a viable option. Administrators are an entirely different beast.