I think the best way to view this feud between them is to look upon the future.
Let's just say 10 years from now, even 5 years, and let's say we are a Prem team, and obviously I'm supposing Billy would no longer be our manager (In fact I honestly doubt he'll be here this time next year, but that's a different matter).
Whom do you think Forest fans then would think of more highly - Billy or Nigel?
Unless Billy brings us up and keeps us there or wins a Cup, I honestly believe it would Nigel that would be held in higher regard.
That's of course if our Billy doesn't do a Preston on us!