I guess you mean fast slide or whatever its called.I don't use it personally but I know many that do.I accidently moved to wrong square several times until I got used to it.Probably a personal preference thing.
Not sure what you mean.If I could see all opponents moves and they not see mine I would most definetly like it
I think I used the slow piece slide until about halfway through my very first civ2 game. Way too slow, and I was on a p133. And I definately don't use the mouse for movements. I've become quite handy at using my number pad to move howitzers along my railroads to my enemies destruction.