Well, if a person showed a talent for writing beautiful pieces of work time and time again, and already showed a love of the characters that the company used, than it would be very easy to just hire them to help new scripts. Of course, they might also run into the problem of the person only being able to use very specific characters in specific plots.
Either way, it really would be a dream job. ^.^
Well, a dream job for some people. I don't know my way around anything Square Enix. Production I.G., on the other hand... ^.^