Compare Two Competing Explanations For A Skill Plateau

Progress has stalled and you have read two plausible-sounding explanations for why, with no way to tell which applies to you specifically. This lays out the mechanism behind each, compares them against the symptoms you would actually expect, and gives you one concrete way to test which is really going on.

<context>
You have plateaued on {SKILL_NAME} after {TIME_PRACTISING} of practice, and you have read two different explanations for why plateaus happen: {EXPLANATION_A} and {EXPLANATION_B}.
</context>

<task>
**Compare the two explanations:**
1. State what mechanism each explanation proposes for why progress stalls
2. Identify which explanation better fits the specific symptoms you would expect to see from each
3. Note where the explanations overlap rather than genuinely conflict
4. Recommend one diagnostic step to work out which applies to your actual plateau
</task>

<output_format>
- Mechanism behind each explanation
- Symptom comparison
- Overlap noted explicitly
- One diagnostic next step
</output_format>