You're forgetting that the monster maul has a much wider head and cutting angle than most mauls. This, coupled with the weight gives the mechanical advantage that makes the monster maul work better in tough wood. I find that there is a point where trying to beat a tough round apart with an 8 pound maul is tougher on my body than using the monster maul and getting the job done with fewer hits (and I can hit the same place more than once consistently
). I don't love swinging the monster maul but it gets the job done when needed.
Also, the splitting force when splitting wood is directed out, perpendicular to the direction of the maul's travel, not down (...I think). And A=m/s^2 or A=m*s^-2 NOT A=(m/s)^2 so doubling the speed does not quadruple the force, it doubles it.
Scott