Teaching a grammar point inside meaningful language works about as well as drilling it on its own, and focused instruction clearly beats leaving learners to absorb a rule by exposure. So your weak rules go into the next chapter's sentences.
One caveat worth stating: the tests in this literature lean toward explicit knowledge, so the measured advantage may not transfer in full to spontaneous speech.
Volume does its own work
Extensive reading in a second language improves outcomes by itself. Reading combined with explicit vocabulary and grammar work does better than reading alone, which is why a chapter arrives with exercises and review cards already attached to it.
Hitting a level on purpose
Asking a model for an A2 story is not enough on its own. Level control tightens measurably once the model is shown worked examples at each level, and that is the recipe we follow.We do that, then score the finished chapter and check that the target rules actually appear in it. A chapter that fails gets one resample before anyone sees it.
What a story cannot do
The story carries the practice. It does not stand in for it. Reading on its own leaves the feedback on your own production unclaimed, and that is the job of the exercises after each chapter.
Getting the most out of it
Start one level below where you think you are. A story you finish beats a story you abandon.
Read the chapter once with the glosses off, then again with them on.
A rule that keeps reappearing across chapters is your profile at work.
Report a chapter that drifts off level. The level check runs on every generation and a report is how we find the misses it lets through.
Under the hood
Rule selection comes from your grammar profile. The generator receives at most three target rules per chapter plus the descriptor for your CEFR band, and per-level exemplars are drawn from our own cheat-sheet pages.Every generated chapter passes a validator that scores its level and verifies the target rules are present. One resample is allowed before the chapter is accepted.
Sources
Norris & Ortega (2000) Effectiveness of L2 instruction: a research synthesis and quantitative meta-analysis. Language Learning.
Nakanishi (2015) A meta-analysis of extensive reading research. TESOL Quarterly.