@clarkperkins I'm a big fan of single return statements for readability's sake. Let's refactor this to: 

```objc
- (MKOverlayRenderer *)mapView:(MKMapView *)mapView rendererForOverlay:(id<MKOverlay>)overlay {
    MKOverlayRenderer *renderer;

    if ([overlay isKindOfClass:[MKPolyline class]]) {
        MKPolylineRenderer *routeRenderer = [[MKPolylineRenderer alloc] initWithPolyline:overlay];
        routeRenderer.fillColor = [UIColor redColor];
        routeRenderer.strokeColor = [UIColor redColor];
        routeRenderer.lineWidth = 4;

        renderer = routeRenderer;
    }

    return renderer;
}
```