And what do you accept as the proof of dates for any of the Didache or any of the books of the New Testament?
I accept nothing as true from the annals of the Roman church. They have been caught WAY too many times creating inclusions and outright forgeries to further their aims. Who is to say that every inclusion and forgery has been found out?
I will accept extant documents from c.250 or before for consideration, but anything beyond that is considered tainted. Beware the leaven of the scribes and the pharisees.
[...] or any of the books of the New Testament?
I do not support the Roman theory of canon, nor do I need to date the Bible. It is protected and proven divine in my mind, by way of incredible encryptions, which being present, guarantee, at least in the main, that the words are true to the original form. From there, the dating is given within the text.