It doesn't always work out that way. Check out Linus Torvalds' discussion of Subversion or Dan Bernstein's discussion of Postfix, for example. Even though Linus and Dan are competent and confident, they were very harshly critical of their "competition".
Indeed, which is why I was highlighting an example of "doing it right" (aka acting like mature professionals). Even when business issues don't get in the way there's still plenty of room for personal and emotional issues to bring down the level of discourse.
