I just came across your account of Dave McDaniel's adventures writing U.N.C.L.E. novels and found it fascinating. However, you have the Ellik joint pen-name for CROWN OF GOLD AFFAIR wrong. It was Fredric Davies, not Fredric Stratton. Stratton -- Thomas Stratton -- was the joint pen-name that the late Buck Coulson and I used for #'s 11 and 12, INVISIBILITY AFFAIR (Originally "The Invisible Dirigible Affair," shortened by Terry) and MIND-TWISTERS AFFAIR. Like Ellik, we were long time fans that Terry knew, although the real reason we got to do the books was that Terry had previously bought two Ace Double novels from Coulson's wife, Juanita, and he had asked _her_ if she was interested in writing an U.N.C.L.E. book. She wasn't, but Buck and I, who'd been collaborating on Thomas Stratton" pieces for their fanzine YANDRO (to which Terry subscribed) for years, decided we didn't have anything to lose by trying. To everyone's amazement, including Terry's, he liked and bought the chapters and outline we sent him two or three weeks later. I've always thought of that and the following book a terrific "earn while you learn" program, neither of us until then having ever written anything longer than a short story.
Also, I can't vouch a hundred percent for this, but it was my understanding that after our two rush jobs, Terry wanted Dave and us to alternate doing the novels from then on, but because of the confidence problems you describe Dave as having, it never came to be. In a subsequent novel, though, Dave did Tuckerize both of us.