people really do wanna believe that tracing is the only way to get to get decent results, dont they?

there are letter where vincent asked for, then talked about his study of Charles Bargue plates which explains to young artist how to get proportions for mass and shadows. at that time they were said to have been taught even in high schools.
the examples they give here aren't too convincing since some major proportions are rather off.

has anyone considered that his drinking may have effect his motor skills from time to time?
it may explain why some were so sloppy and others weren't too bad.