You become good at a drawing. You will practice efficient with a drawing tool that was thought from the viewpoint of brain science.
THE ENGRISH JUST MAKES IT EXTRA CHARMING. 8D Also, for quick get-to-the-fun-stuff; http://www.eggazyoutatsu.net/eng/atarichanDrawer.html There is nothing - I repeat - NOTHING that can replace simply looking at a thing that is there in front of you (in terms of being able to draw stuff and people and perspectives). But this is a pretty fun creative tool to help rationalize space measurements if you ALREADY know which lines to make short and which lines to hide entirely. Will definitely help in animation and posing - not so much in knowing how the human body works and bends as a thing with muscles and bones and stuff.