Sustained attention/visual organization and Cancellation:

The visual field for Cancellation has a big mass of visual images filling up a two-page spread, with no visual or verbal guidance about how one should search through the field in an organized manner to find the target items. Symbol Search and Coding, OTOH, are laid out in grids, with nice, neat visual boundaries for each row. An individual who relies on visual scaffolding to maintain tracking, or organization, benefits from the gridlines on SS and Cd, and lacks them in Ca. If the lower Cancellation score is a genuine finding, and not just a mark of testing fatigue at the end of the session, it might be that the absence of a visual frame impeded her speed and efficiency in the visual search task, or caused her, for example, to skip whole lines, thus omitting possible correct responses.

Average scores:

HG kids can definitely use cognition to power through dyslexia-related tests that non-disabled NT kids complete automatically, resulting in similar scores, but arriving by very different paths. So no, average scores do not necessarily rule out dyslexia in a high-cognitive individual.

...pronounced like the long vowel and first letter of the alphabet...