[kasool]

I agree with the difference you describe. A lot of people who are "naturally gifted" at drawing just have an intuitive sense of what is right, and just are able to draw without thinking too hard. When master artists are sketching the layout of their scene, they're not necessarily explicitly thinking about vanishing points and perspective. With practice, this stuff becomes completely intuitive. Unfortunately this often means that the best drawers are not necessarily the best teachers : )

For the record though, I think pretty much anyone can learn to draw "well".