Send editorial comments on Ian's proposal. I think this info should be put in the Techniques document. Navigation of active elements required because these are user interface elements. If you can't identify an active element for activation, it's useless. Checkpoint 7.5 Allow the user to search for rendered text content, including text equivalents of visual and auditory content.
Users render the text content.
Suppose you have images turned on and search for alt text. You may confuse users by landing on the image. But the text isn't rendered in that case. Checkpoint 7.6 Allow the user to navigate according to structure. No minimal requirement obvious except that navigation is required as an essential functionality, otherwise too burdensome to have to reread the page from top to bottom.