. . . For beginner photographers, shooting and printing full-frame is a good exercise for training one's eye...for quickly learning to see as the camera/lens sees. For the same reason, using only one prime lens is also a good exercise for beginners. Both help them to be aware of what is happening in the corners and sides of the image -- those are important as they define what is happening in the center.
Vaughn . . . .
I agree with this. Eventually one should acquire and use all available tools, though.