As far as I understand it works this way:

First, all views are rendered, including all postprocessing.

Then, view entities and panels are rendered, so they both appear above the postprocessed views but show no postprocessing themselves. I see my flare sprites over your Shade-C HDR effect but the flares dont contribute to the HDR effect itself.

View entities can probably be attached to a view only for rendering them with a certain aspect and arc, and also for rendering them into the target bitmap of that view. That was that thing that Grafton had his problem with.

You can see the rendering order when you check the layers. View entities appear above panels when they have a higher layer, this would not be possible when they were rendered before postprocessing. But views appear always below panels and view entities.