As to issues of intellectual honesty I'm not sure what you are implying.
Yes, I read that paper (well, skimmed it anyway). What I mean by intellectual honesty is that when presenting a case, you should also acknowledge any arguments against it. Here, Doherty has to deal with what looks like a clear statement by Paul about Jesus' physical origins. He does so by saying that we really don't know what "kata sarka" meant. The obvious thing to do, under the circumstances, is to ask how Paul, in particular, uses "kata sarka", especially in this kind of context. It turns out that Paul does use "kata sarka" in the context of one's physical origins elsewhere, and in the same letter. In Romans 9:5, Paul again says that Jesus was Jewish "kata sarka"; two sentences earlier, he describes
himself as being Jewish "kata sarka". It certainly seems to me that Paul's parallel use of the phrase for himself and for Jesus argues strongly that when he uses it about Jesus it means exactly what it seems to mean: that Jesus was physically Jewish. And it also seems to me that if you're going to discuss Paul's use of the phrase at one point in Romans, you'd better address the other occurences in the same book.
Also, is there anywhere in the kind of Platonic literature that Doherty is using as context an example of a spirit being who is said to be descended from a human, in any sense whatsoever?