Show me the oldest copies of the fragments showing the first page. Do some research. And, the 19th century is long gone. Perhaps you need to update your sources.
'We' know nothing of the kind
That head is still stuck in the sand. Denial is not a proof, FTD.
Once again, there is no legitimate reason to doubt any of the Old Testament books or their authors
Why? Because someone chooses to believe so against all evidence? Hey, if you wish to believe so, that's fine with me; just don't present your belifs as facts.
No, actually David's Jewish empire did span a very great area
Again, you need to update your readings.
It was axiomatic because of the authorship
The authorship of many biblical books is based on traditional belief and not on evidence. I hate to burst your bubble, but many of the books purportedly written by the same author demonstrate dissimilar writing style, vocabulary and other elements that betray them as having differet authors claiming to be one and the sam Apostle.
First, having different writing styles means nothing.
If one is writing to a different audience, or dealing with a different subject, it is understandable that the authors style would change.
Two, regarding David's conquest,
Excavations have revealed plenty of traces of the acquistions and expansion of the kingdom of David. There is a clear trail of evidence which accompanies his advance, including the burning evidence of the cities of the Plain of Jezreel....Archaeologists from the University of Pennsylvania have dug up on these sites of ruthless fighting, shattered temples, deep layers of ash on top of ruined walls, ritual objects and pottery belonging to the Philistines. David's vengenance administered a crushing blow to the city which had compassed the shameful end of the first king of Israel, a blow from which it did not recover for many years to come. (The Bible as History, Warner Keller, pg. 196)
Regarding the superscriptions on the Gospels,
The dating of the emergence of a four-gospel collection has often taken its bearings from the particular form of the superscriptions or titles of the Gospels: 'The Gospel according to X'. Martin Hengel argued from this that the titles must have originated, quite early, from the practial necssity of distinquishing among such documents when multiple gospels were at hand in the archives or litugical libraries of particular communities. Hence the titles were not late additions, but belonged to the gospels in their earliest period of circulation and had historical tradition behind them....He believes that the gospels originally circulated individually yet rapidly, so that by the early second century(emphasis added) they were present together in church librries of major centers;...(The Canon Debate, Lee Martin McDonald, James A. Sanders, editors, 2002, pg.278)
I suppose for some such as yourself, however, ignorance is bliss and that is why you choose to remain so.