There may be an inverse relationship between these two quotes - I have heard it said that one of the hardest things about learning 3d CAD is unlearning 2d. Don't know if that is true, but in my own experience I would at least say that my 2d skills certainly did not
help in learning 3d. The first steep climb in the learning curve was getting a handle on
how to think 3d modeling, and it is almost entirely different than how I approach 2d drafting. In fact, I just realized as I wrote that sentence that two key words describe the difference for me: 3d is
modelling, while 2d is
drafting. Not sure that makes sense to anyone else; might just be evidence of my disturbed mind ...