1 point of finesse = 5% damage and 1% dodge chance
1 point of dual wield = 5% damage and 1% dodge chance
putting points only in polymorph and using the extra ability points on finesse gives you the same benefit as though you had put points in dual wield, but instead of getting damage only when dual wielding, you get damage when dual wielding using a a two handed spear and using a ranged weapon all by just putting points into polymorph.