Combined realtime and advanced rendering for offline renders

[DriesV]

I have no idea how feasible this is, but it would be a neat solution in many rendering scenarios.

Often renders are done with advanced control to obtain noise-free images. However, the dielectric or any other advanced transparent material can cause GI splotches that can be hard to get rid of with advanced control rendering.

Say I have a product with a transparent container. I would like to render the product with advanced control.
It would be cool if the container 'region' could be rendered in the same frame with realtime settings (max. time or max. samples).
This way you get the best of both worlds: noise-free product housing and a transparent container without GI splotches.
It would also be a lot less of a hassle than doing separate advanced/realtime renders and compositing in post.

Is this possible at all??

Dries