My reality is that a combination of keyboard shortcuts *and* mouse use is best.
I grab a chunk of text with the mouse, CTRL C/CTRL V from the keyboard for example. Some apps support selecting and moving text with the mouse, which can be done at least as fast as using the keyboard.
This Mouse vs. CLI thing is more emacs vs. vi fanboi nonsense, people work with the tools they like and are comfortable with, a few seconds saved here and there is bean counter false economy...