Although that may be the truth, it's a rather stupid truth. That method is still used professionally, and is needed to be done in order to reach
efficiency in the animation pipeline and to have realistic quality. It was even done in Wreck it Ralph, if anyone has seen it yet, has an opening skit/film which disney animated in 3d, then traced over, and I haven't seen anything more beautiful than that.
On a side note, tracing will also improve your drawing of curves and timing - two very crucial parts of animation.
-R w/ S
I agree that tracing does help to the degree of improvement, as it has helped me improve my artistic abilities, but I was referring to more as the "Tracing over another's work for your own personal gain".
There's been an incident recently that someone copied, frame for frame, another's work and passed it off as his own.
Even if It's been used by professionals, and is an extremely convenient method, my principles stand against it; as do others.
I will consider the method eventually, as that of my curiosity gets the better of me and will edge me to try it out. Nevertheless I think I;ll stick to the ol study method.