Bent Normal maps are also used in a powerful but less traditional way, and that is for Reflection Occlusion / Specular Occlusion. An Ambient Occlusion (AO) map occludes Diffuse indirect light, while Reflection Occlusion is a similar concept, but applied to Specular indirect lighting. Reflection Occlusion works by intersecting the Specular lobe with the visible cone or a cone representing the unoccluded part of the hemisphere described by the Bent normal as the cone axis and the AO amount as the cone angle. This results in significantly reduced Specular light leaking especially when Screen Space Reflection (SSR) data is not available.
Multi-bounce approximation for occlusion is also supported. This means that instead of AO or Reflection Occlusion shadowing the first bounce, we can use an approximation of what many bounces will produce. With multi-bounce approximation, brighter Materials will lose less light, and colored Materials will be made more saturated.