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His test results are very strong all around. Yes, BD is timed. If you wanted to find out more about whether his score was affected by speed, you would probably want to ask whether his BD no-time-bonus score was different from the standard BD scaled score. For example, if he solved most of the items, but not within the time limits, or without receiving bonus points for speed, that would be more indicative that timing/speed was the reason for the lower score. In contrast, if he received this scaled score simply because he didn't generate enough correct solutions for a higher scaled score, but did receive some bonus points for speed on the correct items, that would lead to different conclusions.
FWIW, his processing speed subtest (Coding) is not unusually low compared to his reasoning subtests. Sometimes it's not really pure speed, but more perfectionism--expending extra time tidying the blocks, or questioning the accuracy of his response. Or they may even complete the items too quickly, resulting in careless errors. These are clinical observational data that you would have to get from the school psych.
And while the working memory subtest is lower than the other subtests, again, it's not hugely discrepant. Nor is it by any means below age-expectations (most would classify it as upper end of Average to High Average). Working memory does not always closely track long-term memory/retrieval. He has excellent reasoning skills, both verbally and quantitatively, so high average working memory is probably perfectly adequate for most things, since he likely makes quick associations between incoming information and his existing pool of information, limiting the amount of time he needs to hold it in working memory while he finds a place to file it in long-term memory.
In any case, for both BD and DS, I would be hesitant to read too much into a single subtest, especially in the absence of IRL concerns. These would be more interpretable if you had the other subtest in each index, and thus could obtain an index score in Visual Spatial and in Working Memory, but since this was a GT assessment, and not a learning disabilities/special education assessment, it probably wasn't considered critical.
And I have a background in chemistry and biology as well, though I too have moved onto something different professionally. I see no reason that introducing fluid dynamics or covalent bonding into everyday conversations should not be normative.
