The denials of Peter scene
The story of Luke's narrative sets the scene of Jeshua talking to his disciples from verse 25 of chapter 22. In verses 28~30, he is telling them of making a covenant with them for a kingdom in which they--
those disciples there--would be judges over the twelve tribes of Israel.
Then, while still in that same flow of monolog, attention is directed towards Simon Peter with the request that when he returns, he should strengthen the others. (One interesting note here is the assumption of story knowledge on behalf of the reader, which can be observed in the author's formation of the story--of course that clicks with the opening of that narration's purpose; 1:1~4) It is at this point that in the communication that Peter avows loyalty to Jeshua to which the latter informs Peter that a rooster would not crow until he would have denied him (Jeshua) three times. At verse 39 they go out from the upper room and over to the Mount of Olives.
The story flow of Matthew and Mark have Jeshua and his disciples going out to, or towards the Mount of Olives before Jeshua informs them that they would be stumbled. (on that night [in Mark]) These disagree with Luke in that
1, the topic came up in conversation most obviously after they had left the upper room, and
2, the concepts involved in the communication's introduction and content are distinctly different from Luke's and include strong non-reoccurrent elements. Mark's narrative differs from Luke's (and Matthew) in that Jeshua tells Peter that before a rooster would crow twice, he would deny him three times.
The story flow of the narrative written in John's name is yet altogether different from that of the synoptical view. It agrees with Luke's narrative in that the scene under discussion occured while at the table during the Passover meal. The communicated context, content, and emotion all disagree with Luke's narrative as well.
Up to this point, if we take Luke's report to be historically accurate in detail, we can clearly see the other reports to be historically incorrect. The follow-up portion of this scene in each narrative should also be checked, and weighed in to help form the overall picture. (although it can easily be guessed, that each overall context of each writing adheres well to itself, so that the follow-up verses regarding the fortold event agree with its introduction as looked at so far.)
I will form a conclusion on this soon enough, and if any one following along would wish to do the same, we can each present our conclusions and the case backing them up. I feel it is not in the interest of the nature of this thread to make too much attempt to argue beyond that--we are all sharing and learning.