N.C. Wyeth
ILLUSTRATING A POINT
Famed illustrator N.C. Wyeth, a masterful wielder of the brush if there ever was one, once said, `Painting and illustration cannot be mixed - one cannot merge into the other. The fact is, you have got to drop one absolutely before attempting the other.`
Ref. deseretnews.com/dn/view/1%2C3949%2C%2C00.html
The teacher of my Head Painting class has been an illustrator since he graduated from Art Center probably between 15 and 20 years ago, and now he is merging into fine art painting. He has his paintings in two art galleries, and he says they are selling well. But I think he still illustrates for a magazine. So, using him as an example, I would say that you can do both at once...
But maybe the quote was meant to mean that you can't do a fine art illustration, or in other words, have both a painting and an illustration in one work? I think my teacher is planning on dropping the illustration work completely as soon as he can pay the bills off of his fine art, if that makes any difference. Maybe N.C. Wyeth means that you can't get fully into and successful with fine art until you drop your illustration work, or your illustrators tendencies.