Also in the his article, Couchoud admits that the episode works also as pro-Roman apology. But he recognizes the role of Pilate in securing himself (and so the reader by collateral effect) that the crucified one is the 'king of the Jews':The main protagonist here is Jesus Christ, and the scene wants to make clear that you don't miss who is to blame for the death of the protagonist: not Pilate, but the sanhedrin
This question and answer would be not necessary under your hypothesis (=that Pilate serves only to accuse the Jews). So you have to ignore this question and answer without an explanation (differently from Couchoud's hypothesis).
I am not talking of a 'psychological profile' for Pilate when I point out the problem that your hypothesis can't explain: any Roman ruler in the place of Pilate could kill both, Barabbas and Jesus. This is the point that escapes your attention. So this is a strong clue that the entire Pilate episode was designed from the beginning to show a mutually exclusive Death and liberation: only one has to be the crucified because only one IS the CRUCIFIED Messiah.
I don't understand why you say that I am ignoring that our Jesus (you mean: "called Christ") is Christ.You seem to forget that our Jesus is a "Christ", a messiah. The question what kind of messiah the people want is the core here. You don't even need Leviticus 16 for this point still to be true, even in the scenario I presented. So no, I don't think Couchoud's point is strong.
I agree with you that it is the choice of "the people" that matters in this scene, but for a reason entirely different from your. The choice of "the people" matters because it is made clear that the "people" chose who the people called "king OF THE JEWS". The emphasis is on the Jewishness of the victim chosen by the people: the people was not deceiving themselves, their chosen victim is really a Jewish victim. Not an alien as only the Son of an unknown Father could be.
Probably you don't understand the Couchoud's point. I am alluding above that, for the Epistle of Barbabas, for example, the two goats of Lev 16 allegorize the same Messianic figure: Jesus Christ. So Couchoud concludes that Barabbas can't be allegory of the expelled goat since also the expelled goat is pure and immaculate just as the killed goat.However, you can not use your premises to your case (here that Couchoud's assumption is right that we only see one person, or your premise that the word "insurrection" is meaningless)
How can 'Jesus' be a insignificant detail if even Origen confessed his embarrassment when he wrote that 'Jesus' has to be not the name of a robber as Barabbas? So Origen's words is evidence that the Christians were really embarrassed from the strange fact that the robber is named 'Jesus Bar-Abbas'.Well, no, because I think your premise is wrong. You seem to forget that "Jesus" was such a common name that, by itself, it's a completely meaningless detail. It's this meaningless detail you base your case on. Nevertheless, the name Jesus in combination with what follows (Barabbas or Christ) serves as parallelism, and we obviously look at two possible ways to become a messiah here, independently of whether you accept my whole scenario or not. This means that we do not need to look at a rival Christian sect here, as Barabbas the insurrectionist of a somewhat equal rang to Jesus Christ matches of what we (later) see in Jewish history (Simon bar Kokhba). This means there is no need to assume a Christian background for the parallel figure.
What Couchoud says is that the only reason to overcome that embarrassment is to attack a Christian rival sect. Now, Bar-Kochba is not the hero of a rival and Christian sect. If we had evidence of the fact that the Christians of the time were in relation someway with the Zealots, then and only then I can concede that your exegesis is right (I will do also more than this: I will become a proponent of the Zealot Jesus hypothesis and I would abandon my mythicism). But since no scholar has advanced evidence of an effective relation between Christians and Zealots, then any hypothesis of Barabbas as a banal Jewish messianist is based on pure nothing.