Kishkumen wrote:I believe the witnesses had no expertise to judge the plates an ancient American artifact. I don't know how one gets around that.
I don't see their significance as consisting in any purported Mesoamerican expertise.
Their value comes as an important part of a cumulative case. Together, the Eight and the Three make it extremely likely than an actual material object (the plates, leaving aside the other artifacts mentioned in the testimonies of the Three) actually existed, thus greatly reducing the probability that Joseph Smith was merely hallucinating or simply lying. And the testimony of the Eight increases the likelihood that the supernatural was involved.
Those are both major propositions, and the Witnesses help to corroborate both.