Play that funky music white boy~

 Solid drawing can refer to 2D animation where it would be applied so that 2D animations look 3D, so with 3D animation it seems rather redundant, but this is not so. But solid drawing does not defer to only that, solid drawing in 3D animation helps to ensure that every pose a character may take on in a key frame is decipherable to the viewer.
Something to avoid while employing this principal is twinning, where the poses on either half of the body are identical, making the character appear to be a robot. Sometimes the issues in an animation fail to be apparent. Solid drawing in 3D animation refers to the double checking of the animation so that everything is smooth and unique.

Awesome.