There are multiple objections to raise to this, and I would like to take them in order.
The Death Grip of the "historical" Old TestamentLet me be upfront in saying that I believe that the most damning problems of the LDS position are all upstream from the Book of Mormon itself, in the Old Testament. It is not necessarily a question of the details of what the geography of the Americas looked like in the 7th century BC, it is that the entire OT background of the Tower of Babel and the Lost Tribes are untenable. Without a historically valid OT and its prophecies as something that is still to happen, none of the Biblical primitivism that fuels the prophetic expectations is sustainable. No Tower of Babel, no Jaredites, no BoM as a holistically valid depiction of events in the Americas whenever.
The expectations that OT texts engendered up to the 19th century when Joseph Smith Jr began his work are comparable to the Middle Age expectations of finding the Christian king Presbyter Johannes and overpowering the Tartars, Mongols or Islam through an alliance with him. (Yes, the fact that Joseph Smith Jr did not foresee the damning effects of historical criticism on the OT are a problem for his status as a prophet, but he can have that one as a freebie.)
Notice that this is not a question of whether individual passages in the OT can be salvaged as aligning with the fragmentary record of modern archaeological research. The BoM treats the OT as holistically historically accurate, which it is not, and as a result the BoM is not holistically historically accurate. At present, I do not see how to escape this conclusion.
The Contraction of Reality and Interpretation
Royal Skousen in his discussion of Oliver Cowdery as a scribe has this nice little case from Alma 45:21, where Cowdery, in Skousen's interpretation, fell asleep while writing, thus producing a nonsense sentence fragment. For the purposes of my argument it is irrelevant whether Skousen's analysis is correct or not. The point is that Cowdery heard "they had become exceeding dissenting" and wrote that down. From the point of view of the current text, this was a mistake, and we have an accompanying story: Oliver misheard, was exhausted, whatever. At the point of time when it happened, it was Cowdery's best interpretation of what reality was. The fact that the time T between the shift in interpretation was small is not in itself interesting. Skousen believes that the crossing-out took place immediately, but provides no evidence for that; Skousen's assumption that Joseph Smith Jr had to discharge his translation buffer before they could stop their work for a break only is a blemish on the translation infrastructure and an insult to God's intelligence.
Fast-forward to Stephen C. Harper's discussion of Cowdery's restoration of the priesthood. Harper's statement is worth quoting in full:
I have learned that Oliver Cowdery testified repeatedly that he received priesthood from ministering angels. I believe him. I will use his statements to describe his experiences. Richard L. Anderson wrote that “a careful search of authentic documents on his life discloses an impressive number of declarations on priesthood restoration. These were made during his career in the Church as its second priesthood officer, in the midst of his personal trials and resentments outside of its organization, at his final reconciliation with the Church, and at the closing moments of his life. One may choose to disbelieve such testimony, but no informed person can deny that it exists.” I will review these documents so that all who read will be informed persons. The choice whether to believe Oliver will then be fully yours. I am conscious of his contemporaries and ours who have not believed him. My point is not to prove or disprove that Oliver Cowdery was ordained by angels. I have no more power to prove than unbelievers have to disprove. Any statement affirming or denying his testimony is not proof, but an expression of belief or unbelief. I will simply rehearse and situate his witness historically. And as we remember his bicentennial, I wish to celebrate his testimony and declare that I believe him.I start with the common ground: Richard L. Anderson is right in noting that Cowdery repeated his declaration of receiving priesthood from ministering angels through-out his life, when he was in the Church, and when he was outside. Anderson terms such declarations "testimony", Harper follows him here, and I can live with that terminology. The main thing this tells me is that Oliver was most likely sincere in his belief that he received the priesthood from ministering angels, that it reflected his personal convictions.
But now things become tricky, for Harper continues, "My point is not to prove or disprove that Oliver Cowdery was ordained by angels." I accept this statement with some weariness. First off, I am not sure what difference this makes for a historical reconstruction of Cowdery. Secondly, we were just talking about his testimony, his own beliefs; why are we now talking about how his beliefs match our present interpretation of reality? Finally, I am not sure what 21st century entity the word "angel" is supposed to refer to; I understand what the reference meant well enough with respect to the apocalyptic contents of the NT and the OT, but that notion is antiquated and unhelpful in the same way a four-element theory of chemistry would be to making Scotch tape work.
The next sentence is truly difficult, for Harper writes, "I have no more power to prove [that Oliver Cowdery was ordained by angels] than unbelievers have to disprove." I beg to differ. The onus is clearly on those who want to prove this highly complicated supposition. The listener's power to disprove is infinite, so to speak, since the claim advanced is by definition exceptional, thus outside of common experience, and therefore in requirement of serious argumentative support. Harper proposes an equality of argumentative ground that does not hold. A simple substitution may show this; if we rephrase the sentence to read, "I have no more power to prove that Oliver Cowdery was ordained by the Loch Ness Monster than unbelievers have to disprove it." I suspect Harper would agree that the equivalence of argumentative ground is chimerical and not even particularly useful.
But now Harper slides back, from proof or disproof of reality, to Cowdery's testimony. "Any statement affirming or denying his testimony is not proof, but an expression of belief or unbelief." We already agreed that by "testimony" we would mean Oliver Cowdery's declarations, which are well documented. So denying Cowdery's testimony in that sense is a non-move, because of the documented context. At the same time, I have rejected the argumentative move that people can pick and choose whether Cowdery's declarations refer to reality; rather, I reiterate, that the onus lies on those wishing to show that there is a sensible 21st century interpretation for the notion of "ordination by ministering angels". I understand why there was a 19th century context in Biblical primitivism for this declaration to be reasonable; but again I cannot connect to that 19th century context without more argumentative bridging than Harper provides.
I mention that there are issues concerned with which tribes of Israel were allowed to have which priesthoods, a discussion that is complex and reaches all the way into Hebrews, where Jesus is denied Levitical priesthood powers because he is not of the tribe Levi. I believe for the overall LDS stance this discussion is fatal to Cowdery's claims on grounds of inter-testamental consistency, regardless of who ordained him. But I am interested in Harper's arguments, so I will return to that issue.
Because Harper does not clearly distinguish between Cowdery's interpretation of what he experienced and whether this interpretation is still comprehensible in the present day and age, I find myself agreeing with some of his sentences and not with others. For example, I can agree with Harper who writes later "Still, there was no doubt in Cowdery’s mind that the events [i.e. the ordinations by ministering angels, RCK] were historical." But I cannot follow Harper when he writes "... Cowdery, who of all men knew whether he had been ordained by angels ..." because Cowdery only knew whether his belief that he had been ordained by angels was honest.
I agree with Harper that the question of whether Cowdery's testimony is early or late is a red herring, in some sense, if you have already accepted as ground rule, as I have here, that Cowdery believed his own declarations. But these are strawmen as well; Harper's quote of Charles Dickens finding the claims an "absurdity" finds no response in his exposition. One suspects that the reason that neither Dickens, nor some of the other critics such as Turner in his 1842 book, go beyond the claim of absurdity is that they have not vested themselves fully from wanting to hold on to some historicity of the OT.
The place where Harper loses me again is when he finds himself compelled by Cowdery's testimony to ask for whether to believe Cowdery, which in this context seems to mean whether Harper can lift Cowdery's interpretation into his 21st century interpretative matrix unchanged. Specifically, Harper writes,
The fact that Oliver Cowdery claimed that “upon this head has Peter James and John laid their hands and confered the Holy Melchesdic Priestood” compels me to choose whether to believe him. Witnesses force me to choose.I do not see how this follows. One may choose not to have any opinion at all. There is an existential immediacy to this claim that is unsupported by the evidence presented. This hardly suffices to skip across the "nasty ditch". There is no way to generate realism from an interpretation.