Original sentence: Despite this, and the fact that his book, if proven true, would discredit Christendom as a whole, since the concepts that it attacks in Catholicism are shared by Protestants, this book was, and still remains in some circles, a staple of anti-Catholic polemic.His scholarship, however, is widely regarded as having been clearly debunked
Edited sentence: Despite this, and the fact that his book discredits Christendom as a whole, since the concepts that it attacks in Catholicism are shared by Protestants, this book was, and still remains in some circles, a staple of anti-Catholic polemic.His scholarship, however, has been cleary debunked