Thanks PolarBear. You are right. I shouldn't look at it as bombing the WPPSI. The first thing they did when he started was the block design. My heart sank. At that time we did not know about his vision issues - only that for some reason anything with pictures, he couldn't figure out. So starting with block design was pretty much our worst case scenario. But it DID point us to vision therapy.
Portia, I think I posted with you before about this (not sure) but just wanted to chime in and tell you I had the same experience with my DS who had an undiagnosed vision disorder at the time. It was the block design that told me at least that something was very wrong with how this kid is processing visual information. He simply could not do it. It was such a sinking stomach moment b/c you just knew and even my DS knew something is very wrong here. Funny, I am not a professional in that field (psycho-educational) and I was the ONLY one who put it together and then I was treated like I was crazy for saying it and pursuing it further. I feel for all of the children this happens to and their parents are misled or never have the info/insight to realize that their poor child's eyes simply aren't working together. Anyway, hugs to you and your DS ... My DS will be taking the WISC again in May and I will try to remember to report back to you about how he performs on the block design after 10 months of vision therapy.