Twelve concept clusters, twelve controls. Each page turns the one number a module argues with a fixed drawing into something you can drag — the same argument, but now you can ask "what about halfway between?" and get an answer instead of a guess.
Every reading is derived from the formula the linked module states and cites, not measured on real hardware — each page says so plainly, the same way its module's own analytic labs do. Want the fact without the control? the reference sheets. Want to be tested on it? the recall cards.