The diagnostic half works from the line to the rod to the body — line first, then rod, then body.

• A. Body, rod, line
• B. Rod, body, line
• C. Line, rod, body
• D. Equipment, weather, fish

Answer: C.

Diagnosis starts with what is visible. The line shows the fault first: a tail, a wide loop, a kick to one side, a fly that lands off target. That visible result came from the way the rod moved, so the next question is what the rod did. The rod movement came from the caster’s body, so the last question is which body movement produced it.

This order is the opposite of correction, and deliberately so. Once the cause is known, you correct from the body outward: change the body movement, explain the rod movement it produces, then show the improved line result. Diagnosing from the body first would ask you to guess at a cause before you have read the evidence.

Keep one fault in view at a time. The sequence gives you a route from symptom to cause; it does not license chasing every visible fault in the same pass.

Source

The diagnostic sequence is from Bruce Richards’ six-step fault analysis and correction: Six-step fault analysis and correction. See the CI Study Guide (2025) for the teaching material; terms follow the FFI Fly Casting Definitions.