update docs and perf metrics

examples/README.md

@@ -35,7 +35,5 @@ Demonstrates the router's ability to handle complex orientation requirements, in
 
 ![Orientation Stress Test](05_orientation_stress.png)
 
-## 5. Tiered Fidelity & Lazy Dilation
-Our architecture leverages two key optimizations for high-performance routing:
-1.  **Tiered Fidelity**: Initial routing passes use fast `clipped_bbox` proxies. If collisions are found, the system automatically escalates to high-fidelity `arc` geometry for the affected regions.
-2.  **Lazy Dilation**: Geometric buffering (dilation) is deferred until a collision check is strictly necessary, avoiding thousands of redundant `buffer()` and `translate()` calls.
+## 5. Tiered Fidelity
+The current implementation can use a cheaper bend proxy on the first negotiated-congestion pass before later passes fall back to the configured bend model. This is controlled by `RoutingOptions.congestion.use_tiered_strategy` together with the bend collision settings described in `DOCS.md`.