So in other words, you actually haven't read the Dictionary of Christianity in America, you're just citing the text and footnotes you found in someone else's work. Nice.
In case you didn't know, Frank Schaeffer - who used to go by the name Franky Schaeffer - has an axe to grind when it comes to both Orthodoxy and Protestantism. Or so my friends in the Greek Orthodox Church tell me. Perhaps you've heard of Franky's more famous (and theologically consistent) father - Francis A. Schaeffer? You'd do far better to read Francis' books than to quote from his son's.
Okay - for kicks - let's say there's only TWO Protestant denominations on the entire earth. That's still proof that Protestantism violates Christ's prayer for unity and could not be possibly guided by the Holy Spirit. That's incontrovertible. The Reformation was an elective split, not a compulsory one.