Throughout the 50s and most of the 60s, and for most of the period I can remember before that, the Church was a fairly monolithic institution with a fairly unified Mystical Body of Christ.  You may not have liked what they believed, but that's another question.  Then came the Reformers and the outright revolutionists.  When that occurs --- when a reforming or revolutionizing force sets out to change the status quo, monolithic institution -- who is sowing division?  You may even be RIGHT to seek fundamental change, but in doing so --- and especially in the WAY it's done --- it can hardly be said that the static Church seeks "division" by trying to preserve its existence in the face of efforts to fundamentally change it. Those who seek "reform" or "fundamental change" are the ones seeking to divide.  Indeed, not merely divide, but marginalize.  And that's what we have now.