Mouse issues when hovering over certain areas
I'm not sure if this is the same issue, but just in case it helps you or anyone many years later, this is what happened to me and how I solved it.

I use a larger than default cursor from the accessibility menus because otherwise I can never find the darned thing. On my Macbook Pro (new machine) I have been frustrated by the mouse feeling like it is wading through treacle when I move it over an area with lots of links in Chrome.

The right hand side of a Stack Overflow post would be a great example as the cursor is changing from arrow->hand->arrow over and over again as you move the cursor across the related links. Compared to moving the cursor over the empty space next to it I would have to move the physical mouse 2-3x as far on my desk.

I seem to have just solved this by changing the cursor scaling in the accessibility menu to a different (but similar, non-default) value.

From interrogating the values with

defaults read com.apple.universalaccess mouseDriverCursorSize

at the command line I have noticed that some values cause the problem and others don't. For example the default and max values of 1 and 4 do not cause a problem, and nor does 2. I did see the problem with 2.096360005605382 but its not just about being an integer as I didn't see the problem with 2.577354260089686.  I have no idea what this information means.  Perhaps some sort of cursor scaling performance bug with specific cursor sizes?

Anyway this may be unrelated to your issue as your pointer does look about normal size in those videos, but you could try playing with this setting.