Engineers and other highly intellectual people tend to struggle with the "just eyeball it" part of flying. They tend to get bogged down in the theory of all the aerodynamics so they have a lot of difficulty in primary. Some of the most difficult students I've ever worked with were the type that over thinks everything. In the classroom they get it fine, but once they walk out on the ramp and lose 50 IQ points they are hopeless.
When I teach students, I adhere to the KISS (keep it simple stupid) as much as possible. In the airplane, a new student has the learning potential of a high functioning Downs Syndrome kid. All your lessons for the first 10 hours need to be geared for that level of intellectual potential. In an emergency, even a veteran pilot will loose his ability to exercise his higher order brain functions.
A trucker who has driven a loaded trailer down a mountain pass (or a surfer, fishing boat captain, or football player) isn't trying to calculate anything, but is instinctively able to "see" where their angle of descent, rate of turn, and speed will lead.
Thats not to say that the theory isn't important, it absolutely is.