Indeed 
As I said I don’t have experience with it, but in general most friendly for computer resources is when you make a patch of grass for eg. 15-25cm radius and you toss this around. You can check this topic.
Sure this is nothing more than a sparse point cloud of this object. The thing is that it swaps it at render time with correct geometry - every scattering plugin in every other host does this. RN also does this currently for Octane and VRay so you can render without “baking” into the document and saving tons of HDD space and RAM on render time for you. I don’t know how Flamingo was doing this but I guess it was a Flamingo restricted feature as Custom Render Meshes in Rhino aren’t using instancing so you end with bloated RAM on render time.
Serdeczne pozdrowienia 