CSS/ATER would not enter into the point above, as it is a non-standard way of doing the calculations.
I try not to get involved between KS/Jed/Zeus/Bocjin about this. It is very technical. However, in reading through the letters, it is crystal clear that F knew his calorimetry. Every angle and aspect of it. He even wrote a book about it. He could spot other researchers errors at a glance. If anyone had issues they turned to him.
Within this perspective, I find it interesting that KS claims all CF calorimetry is/was wrong. I wonder what F would have said, were he still around to read that? SRI reads LF, and I am sure they took exception to that blanket statement also. Maybe KS did not really mean to say it that way.