able to dump mixed cargo if dumping area accepts all onboard mixed cargo

Let trucks bypass sorting if a area accepts all mixed cargo onboard
EG truck has rock and dirt mixed cargo and i have a dump area that accepts dirt slag and rock it can bypass sorting as it has 2 of the 3 onboard.
it might be to "Breaking/Headache" but some form of "I know its rock and dirt onboard just dump it, dont sort it", be an option for Terraforming
could be a cheese way around sorting as i would presume it would fall back on old style of (technically) trucks being able to sort their load, unless a new material is implemented "mixed" that wraps them in case of later removal would still need sorting.

I agree that it should be a mixed cargo product in itself, that way you could store it.....and transport it with trains :)