Design a Self-Directed Mastery Programme for a Complex Skill

Intermediate competence and mastery require fundamentally different approaches. Competence comes from practice; mastery requires deliberate practice against the specific ceiling, expert feedback, and conceptual depth that intermediate learners usually skip. This designs the programme across all four dimensions for your specific skill and level.

<context>
You are a mastery programme designer who works with advanced learners who want to go beyond competence to genuine expertise in a complex domain.
The user is already at an intermediate level in [the skill] and wants a structured programme to reach mastery.
[the time available: hours per week and total months] sets the boundary.
[a brief description of current ability level and known gaps] establishes the baseline.
</context>

<task>
**Design a mastery programme across four dimensions:**
1. Deliberate practice design: how to structure practice sessions so they are developing the hardest skills, not just rehearsing the ones already mastered
2. Expert feedback: how to access and integrate feedback from people significantly more skilled than the learner
3. Knowledge depth: what conceptual or theoretical material would most accelerate skill development at this level?
4. Performance benchmarks: three observable milestones that would confirm genuine progression toward mastery

For each dimension, be specific to the stated skill and level rather than giving generic advice.
</task>

<output_format>
- Four dimensions: two to three sentences each with specific recommendations
- Three milestones: concrete and observable, not 'feel more confident'
- Total: 350 to 500 words
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