Note: I posted this identical question, over on the Maxon RedShift General Forum.

This isn't entirely a RS question, however, my RS material specifically relies on using many Vertex Attribute nodes, so there is an important corollary.
I've noticed that if I drag a polygon selection tag, into an existing vertex map field, the resultant "variable tag" absolutely chokes the viewport performance. There must be some horribly inefficient process C4D is using, to generate the vertex map from the polygon selection, in realtime. However, if I simply highlight those same polygons, then generate a new vertex map, there is no more slowdown in performance.

Does this make sense to anyone else?

So, is there a way to add polygon selections to an existing vertex map, without having to just drag the polygon selection tag into the vertex fields?

Thanks!