Improving physical accuracy of volumetric fog

Working with Voluemtric Fog in 4.27 in an interior scene, creating ‘god rays’ from Stationary Spot Lights.

On close inspection and having worked with them for a few weeks now I am wishing there was some way to improve the physical accuracy. For one thing the ‘rays’ are not physically correct in that they act like a stencil shader, any objects that are occluded by the ray in the background get lit as though the light was shining directly on them. Has anyone else expereinced this?

Is this simply a limitation of real time volumetrics or is there some way to improve this?