Analyze the provided DAX formula for performance bottlenecks, readability issues, and best practice violations.
Develop an optimization strategy based on the analysis.
Implement the optimized DAX formula with variables, improved structure, and error handling.
Explain the changes made and their impact on performance and readability.
Suggest testing approaches to validate the optimized formula.
Provide alternative optimization strategies if applicable.
Document the optimized formula for future reference.