I Think I Figured Out the Chain of Events Which Led to the Misreporting of Marcion's Theology

Just briefly stated, it goes something like this:

• we start with Stuart George Hall's identification (of Praxeas of Tertullian's Against Praxeas) as Irenaeus
• as Hall notes "the crime of Praxeas (= Irenaeus) is that he 'crucified the Father' by denying the personal distinction"
• Marcion's theology assumed a distinction between Son and Father
• when Irenaeus reports on the beliefs of Marcion he 'plugs' in their redemption formula into his basic assumption that there was no distinction between Father and Son

as such you end up with this monstrous statement at the beginning of Book Five of Against Heresies:

And vain likewise are those who say that God came to those things which did not belong to Him, as if covetous of another's property; in order that He might deliver up that man who had been created by another, to that God who had neither made nor formed anything, but who also was deprived from the beginning of His own proper formation of men. The advent, therefore, of Him whom these men represent as coming to the things of others, was not righteous; nor did He truly redeem us by His own blood, if He did not really become man, restoring to His own handiwork what was said [of it] in the beginning, that man was made after the image and likeness of God; not snatching away by stratagem the property of another, but taking possession of His own in a righteous and gracious manner. As far as concerned the apostasy, indeed, He redeems us righteously from it by His own blood; but as regards us who have been redeemed, [He does this] graciously. For we have given nothing to Him previously, nor does He desire anything from us, as if He stood in need of it; but we do stand in need of fellowship with Him. And for this reason it was that He graciously poured Himself out, that He might gather us into the bosom of the Father. [Irenaeus Against Heresies 5.2.1]

The problem with Irenaeus, as anyone who has ever read his writings can acknowledge, is that he is utterly incapable of 'seeing the world through someone else's eyes.'  He assumes the categories of religious truth as already established (= denying the distinction between Son and Father) and here proceeds to say that the Son (= Jesus) was unknown to the Jews and the Jewish scriptures, that he did not make man.  The Marcionites actually claimed that the Father was unknown and the Son known.  Irenaeus (a.k.a Praxeas) is however unable to accept this distinction and fails to report it because for him the Son and Father are indistinguishable.

Jesus was the creative Word even for the Marcionites.  The failure arose in the reporting of Irenaeus and because of the error (even Hippolytus acknowledges Irenaeus made error in his reporting) Clement could condemn the heresy of 'Marcion' given the fact that Irenaeus didn't get his facts straight.  Marcion was indeed the embodiment of the early Roman and Alexandrian Church only warped by means of Irenaean rhetoric.