To give a little more, attentiveness data would only tell me the student is, for instance, reading a text passage. It offers no insight into how they read the text or to what degree they are applying any instructional concepts to the text. This is useful for instructional purposes (if delivered to the teacher in such a way that they can quickly scan the room and grok what’s happening - but that’s getting into AR territory), but it doesn’t do much for the larger goal.
Assessment can give me that kind of information; hence, my belief that making instruction-based assessment more globally trustable is the key component.
Again, I would love to see something like this come to be. I’d love to jump ship and work on it full time. It would not only provide significant academic advantages, but also make increased teacher compensation politically palatable. If we can measure teacher effectiveness, then we can reward it. If we can’t, we use tenure.