Actually, mousethief, the way I read the historical references that you cite, there must have been a widespread tradition of instrumental music in the Christian church immediately prior to the Protestant Reformation; otherwise, Wesley, Luther, et al, would not have had anything against which they could object.

I can't find it online but I remember reading one of the reformers calling organs "a papish novelty" or some such thing. I think maybe the folks at Trent weren't terribly representative in that respect. Or the organs were just becoming popular in some Catholic places, and the folks at Trent, like the Reformers, were reacting with horror.