Status: IN
The second-order effects of per-problem isolation (tooling unreliability, undetectable naming drift, convention divergence) are invisible at runtime because each solution is executed and judged independently in the LeetCode submission context.
Isolation effects are architectural (cross-solution) but the execution model is per-solution — they can only surface when the test harness's cross-solution imports encounter misnamed exports
Depends on (SL): isolation-creates-undetectable-inconsistency, repo-optimized-for-submission-not-engineering