I could say "Why oh why does the AV add verses to the bible, why did they tamper with the text?". This approach is not very helpful in either direction because it presuposes the original text.
It is a question of fact as to what was the original text that has to be decided, after that it is possible to consider whether a version adds to or deletes from the original.
Free Church of Scotland
"Surely, we wish to be orthodox, but we must first learn what real orthodoxy is. Surely, we wish to be progressive, but we must first have a basis to progress from."