try:
    result = iterator.iterate_to_targets()
except RuntimeError as e:
    print(f"Model validation failed: {e}")
    print("Check model connectivity and initial configuration")

if not result.converged:
    print(f"Failed to converge after {result.iterations} iterations")
    print(f"Final max error: {result.max_error:.2f}%")
    print("Suggestions:")
    print("  - Reduce damping factor")
    print("  - Increase max iterations")
    print("  - Check initial configuration")
    print("  - Verify target tensions are achievable")