Glen Keane is well known and respected as being one of the best hand-drawn animators. In fact, Glen Keane has even been credited as being the 6th most influential Disney animators of all time. I think one of the most important things about him though, is to remember how he handled the production of Tangled. Without having any experience with 3D animation, Glen Keane helped make Tangled a global success.
While other companies were switching over more and more to 3D animation, Glen Keane was an avid supporter of hand drawn animation, claiming that it would be impossible to translate the whimsy and attractive of hand-drawn characters onto a digital canvas. Keane had to change his opinion though, when he was faced without another medium to choose to use. In 2003, Keane was given approval to make a Rapunzel project, however he was only given approval with the stipulation that he it be created using computer animation. Keane was reasonably upset about this, because despite having over 30 years of experience animating, he had zero experience with computer animation.
Tangled has been the most expensive animated movie made to date. It was even more expensive to produce than Avatar. I believe that one reason the film was so expensive to produce has to do with Glen Keane’s involvement. He refused to accept less than perfect on the smallest detail during production. “If the animation was too stiff or unpleasant, Keane sent it back. He’d draw what he wanted with his own hand and not accepted the scene until it matched his artwork“.
History of animation blog 