The math specialist who had assessed him started explaining the tests,showing page after page of correct answers. She then looks at me and says "Now, normally you would think 93% was good but...". DS missed a double digit addition problem. I see what he did and how he got it wrong though I am not sure why he did that, this was a problem type that he had been able to do for quite a while in his head. Anyways, since he continued on his path of incorrect reasoning when she asked him to explain it she used that to deduce that he did not have any real semblance of math sense or understanding.
The math specialist is engaging in selection bias. She had a pre-formed opinion of your DS's abilities, and she has chosen to lock in on the bits of information that reinforce that opinion, and ignore the other 93% of the test that says otherwise.
Ask her if she thinks dinosaurs were hunted by humans, or if 9/11 was an inside job.
