Quote:What does the arrangement of the pads have to do with anything. The only reason why large pads are used at the top and bottom of mice is convenience.
The math in terms of simple dry friction also isn't too complicated. You have 2 surfaces, the feet and the mousepad together they make mu.
Friction force=mu(friction coefficient for that combination of surfaces)*F(normal to the surface) or just the weight that you push down+ weight of the mouse
static friction being the bigger concern as it's the larger force to overcome.
Changing the area of contact doesn't change the force of friction nor does changing the placement of the pads on the mouse, under this model.
In more realistic complex setups in which friction is changed by contact pressure mu and go up or down with more pressure, temperature surface consistency, contamination etc which makes it very case specific to make any generalizations that one way is clearly better. Large mouse pads are used simply because they can draw more gunk without losing as much effectiveness, leading edges that gather containmates vs the amount of pad making contact with the surface is better given larger mouse pads.