tongue chewing wont do shit. the back portion of the tongue seems to be controlled by the genioglossus muscle. contracting this muscle lifts the back part of the tongue and lifts the hyoid and other surrounding tissue along with it. the tongue is not a simple organ, just look at a diagram. the tongue doesnt move in isolation because its a part of a series of other oral muscles that pull on eachother. tongue chewing wont do shit because to actually improve the posterior strength you need to engage the genioglossus which is used to execute a proper swallow and as i said in my previous thread mewing is essentially holding the tongue perpetually in the swallow position. and also dont forget that mewing is mostly cope after puberty because the tongue isnt strong enough to force growth its only capable of guiding proper facial growth.