I think you hit the nail in the scrotum with this:"People who belong to a given tradition often find themselves in disagreement with parts of it, especially as they learn more about their tradition's history and doctrines."
That's me every Saturday in Church. It put me on shakey ground for a bit, until I decided that I'll beleive what I belive, and not worry about the rest.
As far as pluralism vs. ecumenism, is it perhaps acceptance vs. tolerance?
I love that image on your blog banner, by the way.
Waaaaaiiiiit a minute-- SATURDAY?? What the hell kind of Christian are you?
Pluralism comes in many forms, which makes it hard to pin down. Ecumenism also comes in many forms (the term "ecumenical" originally had-- and arguably still has-- a decidedly inter-Christian valence), which makes it equally hard to pin down. The short answer to your question is: "Generally speaking, yes. But the devil is in the details."