From what I gather, we alrady have the text of Sappho's Hymn to Aphrodite (alias Sappho 1, the only poem we have complete) complete and uncontroversial (save for the bit in cruces,
τίνα δηὖτε πείθω / ἄψ σ' ἄγην, which the P.Oxy. doesn't seem to help settle). I found an image of that papyrus:
It only gives a few letters in the middle of lines. So am I right in my impression that this papyrus was, as far as our knowledge of the poem goes, utterly useless, or were there any controversies in the text as reported by Dionysus of Halicarnassus in
Περὶ συνθέσεως ὀνομάτων (aka
De Compositione Verborum) that I am not aware of and that were settled by deciphering the papyrus and identifying it as Sappho 1?
According to Campbell (see note to this poem), one line of this papyrus reads
.]ψ σ. ἄγην[. It should be this line:
In this, I can clearly see
ÁΓΗ, surrounded by what has the looks of a
C…N. But where is the psi? I cannot find any trace of it in there. Since the psi would be like THE contribution of this papyrus to our knowledge of the poem's text, suggesting the
ἄψ σ' found on B.A. and Greek Wikisource, the question now becomes: how did the psi pop up? Can anyone see it in the image? Was something done to the papyrus that made it appear clearly? If so, what?
One small contribution, besides the one in the other update (if the psi was actually there), is that, from what Bergk says, all codices had a zeta in ὐπαζεύξαισα, whereas the papyrus clearly has a sigma-delta cluster in the line
M.L. West (more info about him here) limits the importance of that psi by attributing it to a possible correction from the following line, and seems to favor Edmonds' solution from the critical note he offers.