I think if you need to measure this kind of thing, you're missing the point in the first place. I don't want to be chasing some absolute productivity metric, I want a setup that doesn't break my flow. For many people, reaching for the mouse breaks their flow and feels wrong, which is oftentimes worse than being a second slower, because it takes you out of the mental frame you were in.
For me, using my mouse while I'm working feels natural, so trying to change my workflow to learn how to navigate everything by keyboard would be a huge amount of extra effort just to maybe possibly save a little bit of time in some situations.
For me, using my mouse while I'm working feels natural, so trying to change my workflow to learn how to navigate everything by keyboard would be a huge amount of extra effort just to maybe possibly save a little bit of time in some situations.