Just curious, why do you feel a hover effect helps in this situation? As an indicator that the pointer is where you expect it to be? How does the hover effect help in cases of shaking hands that cause the pointer to move upon click?
First, I use many pointing devices. With my home standing desk, I use an Evoluent vertical mouse. With my workplace sitting desk, I do better with a trackball (it's huge). When I need to take my laptop on the road, I just use the trackpad. They all have their pros and cons depending upon the task at hand.
I think the hover effect helps by making the click a more reflex-driven event. Even if my cursor is skittering about a little bit, a mouse-over effect helps the lower parts of my brain "pull the trigger" at the right moment. I'd describe it as a lot like playing an FPS or some other fast-moving action game. Sounds lame and totally unscientific, I know, but I definitely notice the difference.
That's correct. Adding a tasteful mouse-over effect also serves as a nice additional visual cue.
(Speaking from experience: I have a very shaky hand due to an old injury.)