Doherty tops is hand to show his ignorance when he quotes Hemut Koster, major textaul critic.
Only in Justin Martyr, writing in the 150s, do we find the first identifiable quotations from some of the Gospels, though he calls them simply "memoirs of the Apostles," with no names. And those quotations usually do not agree with the texts of the canonical versions we now have, showing that such documents were still undergoing evolution and revision. Scholars such as Helmut Koester have concluded that earlier "allusions" to Gospel-like material are likely floating traditions which themselves found their way into the written Gospels. (See Koester's Ancient Christian Gospels and his earlier Synoptische Uberlieferung bei den apostolischen Vatern.) Is it conceivable that the earliest account of Jesus' life and death could have been committed to writing as early as 70 (or even earlier, as some would like to have it), and yet the broader Christian world took almost a century to receive copies of it?
The problem is he quotes Koester as an authority. One would think he will Koester as an autority. But in the next breath says AD 70 is early, although concievable as the date for the first Gospel. But Koester himself is the guy who says that people were writting Gospels as early AD 50.Just see the same source.