I can personally attest that my mouse and my eyes are only very loosely correlated, maybe 50% at best.
(Much of the time I am using hotkeys, and when I am actually using the mouse it is often flitting around in my peripheral vision where I can see it but don't focus on it)
When I'm reading Hacker News my eyes are on the comments, the mouse pointer is on the left or right side so it isn't causing any distraction. I do it all the time. Sometimes I also highlight what I'm reading, mainly if I'm multitasking and it's a long text, I want to know where I started last time I lost focus on the text.
Re: highlighting, I do the exact same thing. Has always made me wonder about an add-on or something that could handle that in a way that gave it advantages over the highlighting method?
Then again, highlighting is low-tech, easy enough and works fine. Maybe I'm looking for an idea that isn't there.
(Much of the time I am using hotkeys, and when I am actually using the mouse it is often flitting around in my peripheral vision where I can see it but don't focus on it)