For one thing, I recognize that it is a device. Cartoonist Gary Larson is famous for his frequent use of it. Larson is revered as a successful communicator. Why would I diss Mark for something that I appreciate in Larson?What I am wondering is what would distinguish this literary device you are describing from sloppy writing.
Second, in what way is it sloppy? Jesus has predicted his third-day rising three times already. Why not condense a fourth such episode? There may be other kinds of interest in the omitted scene's particulars, but if the unserved interest is unrelated to the audience's appreciation of the unfolding story, then how could the omission be a flaw in storytelling technique?
Finally, the omission is harmless. If the omitted incident is fictive anyway (as I suspect that the conversation between Adam and the Woman is, for example), then so what if it's omitted? If the incident really happened, then how is its omission any more a flaw than the omission of everything that happened in Jesus' life before he met John?
Could be. How much alike depends on whether or not his or her lapse effectively advances the story, reveals character and coincides with what other authors do on purpose.If an author literally forgets exactly what s/he wrote in a past scene and therefore does not quite "recall" it correctly in the current scene, would the result not look very much like the literary device you are pointing to?
Mark does foreshadow 14:58. This is an instance of hearing without understanding, just as Jesus discussed way back in chapter 4. There is found another jarring line (from the Isaiah passage Jesus mentions) about how otherwise people, understanding, would be converted. Paul, too, considers that if people had understood, then the persecution of Jesus (events like the trial) would not have happened.Foreshadowing, for example, can scarcely be the result of the author accidentally having alluded to the same event twice, ...
With full certainty, I can't. All I can do is note that this "accident" serves the story surpassingly well. That leads me to the dichotomy that either Mark knows what he's doing or else he's lucky. I'm not big on luck, a personal failing, no doubt.So how can you tell those done on purpose from those done by accident?
"Your mileage may differ" acknowledges that your appreciation of Mark's craftsmanship may be less than mine. Yes, if Mark lost the plot, literally, in a work of about 11,000 words, then that, too, would explain it.