If to make the wood finishing materials on both sides then the warping will be prevented or reduced. It is not truth because it is impossible to prevent or reduce the warping of the material just with processing both sides. The reducing of the wood is happened because of a shrinking more tangentially than radially. Here moisture vapor will still works so the same degree of warping will appear. The side that is more exposed to watering and drying can cause the hindered warping. That is why tabletops that all the time have a contact with spills and water need the frequent finishing when it starts to serve badly.