I find this really annoying that if you dimension a 3d model and go back and modify the solid you lose association.
I run across this mostly when I use the "Modify Solid Entity" tool
Taper face, cut solids by curves...
I can understand certain modification that would cut a face of chamfer but not all dimensions should be lost
So when you modify a solid in some fashion does it totally replace the geometry? That's the only reason I can see this happening.