http://mcc457.tumblr.com/post/12738...s-forentilex-been-doing-character-designs-for The question is how do you do a speed draw?
For speed art, it's all just sped up in post, but to get fluid and organic lines you just need to practice making the outlines in one stroke. Not the whole outline, but sections. Lineart is dependent on varying line thickness to give it a detailed effect. The more you practice the faster you will become.