I must say that the psychologist sounds completely insensitive!
His processing speed is average, while the other scores are high. The tester could calculate the FSIQ w/o coding and that will be similar to GAI index from teh WISC-IV. In our area, for example, gifted schools want to look at the scores w/o processing speed. They are also interested to see if a procesing speed is too low which could indicate potential problems.
My DD was tested at 4-10, and she also did not make a good connection with the tester. She seemed to rush through the process (my dd, and the tester did not motivate her to do more). She got similar WPPSI scores to your ds's. Just today we got her score, we had her retested with WISC-IV at 6-7, and her results were MUCH higher. This time she loved the experience!
I have heard of testers interrupting the test after a subsection if the child seems to tired or distracted. The fact that the tester did not do anything about it, makes me think that the results are probably an underestimation of your ds's true abilities.
