I disagree, Jim D. If the results are in fact an artifact of the methodology, how else to say so, and why not say it? It doesn’t say anything about the motives of the person using the methodology; anyone can make an honest mistake, and that may have been what it was.
I’m reminded of Andrew Wiles’ first attempt at proving Fermat’s last conjecture. After presenting his work at a conference, he wrote up his proof and it was refereed. One of the referees picked up a mistake, which meant Wiles had to go back to the drawing board and correct it, which took quite some time. But he accepted that his initial proof was an artifact of his erroneous methodology.
Did that mean his reviewer had made a “serious attack”? Did it mean that Wiles was some kind of scoundrel or incompetent? Should the reviewer not have pointed out the error and described it in detail for what it factually was?
Honestly, this kind of attitude is exactly why people have so little confidence in, and respect for, climate scientists. What’s wrong with directly addressing a possible error in methodology? Why is that framed in terms of being a “direct attack” and “less than objective? To me, it just seems like normal science. If Dr. Francis thinks Dr. Barnes’ critique is incorrect, then she should simply show why there is no error in her methodology. And if she can’t, then she needs to go back to the drawing board just as Andrew Wiles did.