Just a couple of presumptions in the field of textual criticism that i wanted to throw out there.
The closer to the original the less mistakes in the manuscript…
This is not necessarily the case. Without knowing the care that went into each copy there is no way of knowing how good of a copy it was.
For instance 2 of the copies may be word for word and 3 may be more like paraphrases. That really depends on the premise of the copier going in to make the copy.
If i am given a list to copy that does not need every word conveyed i will approach the task of copying differently than if i had to copy a set of instructions where every word counted.
It would also depend on the skill of the copier.
So age alone can’t give us any degree of certainty regarding how well and literally the source is copied.
I have also heard folks start off by saying something like “the mistakes that were made in the copies would be carried on in the later copies.”
But this presupposes that a person is incapable of copying something without making a mistake. I don’t think that is as proveable as we are lead to believe.
I worked in editing for a while, and can tell you that it is possible to make a word for word copy of an original document without mistakes. And this was working with documents of much less imporatance than the Scriptures.