Party 'A' magnifies and adds to certain verses while diminishing others.
Party 'B' magnifies and adds to verses Party 'A' subtracts from while also diminishing from other verses.
And this is not just between Catholics and Protestants, it's between every self-identifying sect out there.
No.
Revelation 22:18
For I testify unto every man that hears the words of the prophecy of this book, If any man shall add unto these things, God shall add unto him the plagues that are written in this book: And if any man shall take away from the words of the book of this prophecy, God shall take away his part out of the book of life and out of the holy city, and from the things which are written in this book.
Jeremiah 27
[14]...hearken not unto the words of the prophets that speak unto you...for they prophesy a lie unto you. [15] For I have not sent them, says the LORD, yet they prophesy a lie in my name; that I might drive you out, and that ye might perish, ye, and the prophets that prophesy unto you.
Romans 16:17
Mark them which cause divisions and offences contrary to the doctrine which you have learned; and avoid them.
Of course, the doctrine here is biblical doctrine, not man's doctrine.