[barsky]

Possibly, but graphic design and type design are vastly different fields. A good graphic designer isn't necessarily a good type designer.

[mortenjorck]

Indeed. A good visual designer should know how to take a typeface apart, but you really need to become a type designer to put one together.

[sprokolopolis]

While this is true, type design will make you a better graphic designer. Designing a font is one of the better ways of training your eyes, becoming sensitive to subtlety, trusting your optical perception over raw measurements, learning about the interaction between shapes and space, etc.