that's a clean answer thanks. the 85% rule for BKT routing is more principled than most. the one thing i'd still watch is wether summit mastery still holds or decays over time, since BKT can't tell "build the schema" from "learned to pass the gate". thanks for the detail.
curious how the tutor handles a kid who's confidently wrong. from the description the ladder kicks in at the first sign of struggle, which sounds like it's built to prevent mistakes rather than use them. kapur's productive failure work points the other way, students who commit to a wrong approach and then get shown exactly where it breaks tend to keep the concept. the ones who got steered away before making the mistake don't.
does bloomybot ever just let a wrong approach play out and do the postmortem after? also when a struggling student gets rerouted to an easier skill, can you tell that apart in your data from one who was thirty seconds away from the useful kind of failure? the summit gate tells you they arrived. it doesn't tell you whether the help in the middle did the teaching.