Optimizing Corridor With Multiple Assemblies to Create Berm Based on Variable Grading Criteria

[arander5343597]

I'm trying to build a berm around a large tract of land in Civil 3D. The berm, in some places, requires cutting down some along an existing ridge, while at other spots contains 100% fill built up from the land. My design profile (red) is shown here with the existing (ATTACHMENT: PROFILE1.jpg).

The assembly I am trying to add is a 12-foot wide roadway that ties into the existing surface at 3:1 (ASSEMBLY1.jpg). At locations where this proposed grade is above the existing grade, that works just fine, as shown (ATTACHMENT: SECTION1.jpg). However, where the proposed road surface is below the existing grade, I have to create a separate assembly (ATTACHMENT: ASSEMBLY2.jpg). This assembly consists of a standard crowned roadway, a LinkSlopetoSurface sub-assembly at 0%, and once that sub-assembly meets the sidewalls of the EG, grading from there at 3:1 down. In action, this section is shown in SECTION2.jpg, where you can see the ends of each side of the roadway then grade to the existing berm, and then down at 3:1. This is to prevent grading up from the edge of road and creating a roadway nestled in a V-shaped valley. My question is this: back in PROFILE 1, you can see how the proposed profile is sometimes below EG and sometimes above. I get that I can change the assembly based on stationing along my alignment, but is there an assembly that can be built that can do both "on the fly"? i.e. it would analyze if the edge-of-road is above the EG, and if that's the case, simply grade 3:1 to EG. If the edge-of-road was NOT above EG, it would grade 0% to meet the side-slope, and THEN grade 3:1 down.