There seems to be a problem/limitation with the way view clipping works with the coordination models linked into Revit.
In my case, I tried all of the previous suggestions: Phase, Discipline, and VG tab check box as well as minimizing the number of linked coordination models (in case there was a resource limit), different view scales, Wireframe/Shaded display, etc. Nothing worked until I set my Far Clip Offset way deeper than I want and various items or all items appear depending upon the depth.
I'm trying to show Shear Wall penetrations, so I'm using an Elevation (Sections work the same way) that starts at one face of the wall and ends (via Clipping) 12" away. I really don't want to see anything outside of this range, so it isn't very helpful that I have to set the Far Clip Offset to 10' before I see a number of the elements that are actually there (in my case a group of conduits penetrate the shear wall and then go off on a diagonal). Since there's no cut line, everything just blends into a colored blob since the conduits run off at the diagonal.
What I think is going on is that the elements don't appear in a 2D Revit view at all unless there is at least one planar surface inside the range of the view. In my case the conduits only appear once the end of the conduit is within the range of the clipped view, which is why only two conduits appear when the Far Clip Offset is set to 2'-0", but all 10 show up once I've increased the Far clip Offset to 10'-0".
Hopefully, this limitation can be fixed since it does not affect a tightly section-boxed 3D View.
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