You have to understand, JimT was a very specific breed of writer. Patient would say some, impassioned perhaps, though some would say he was simply dogged, or maybe a bit insane. Either way, he was responsible for many a-headache amongst coders, with Bess/Ben being the most monumental completed project to date, and one that Fenco would hesitate ever doing again.
Even Embry, a relatively modest character project, has claimed the souls of a few writers. Whether it was the burden of trying to measure up to his quality of writing or biting off more than they could chew, these writers would eventually break down and give up.
I for one would not go to our other prominent writers to work on a character that was not their own.