This is my opinion for the soft sponge blocks..
Enough pressure should be applied to conform the sponge to the surface
being sanded. Then treat it like a contoured block, that is move it
only along the object .
Realize that were more pressure exists the sanding action will be
faster. So if you are sanding an ogee edge the top of the curve will
have more material removed.
Dry, allways sand wood dry.