With the new Dyn 1.3, this has now been added as a built-in node.
However, I’m having difficulty using it. The idea is to place grids at some pre-determined positions (e.g. randomised). It seems from the documentation that its inputs are 1: the curtain wall, and 2: a list of surfaces.
However, if I do that (surfaces perpendicular to the curtain system surface at the positions I wanted the grids) it gives me just a list of nulls - no error displayed, nothing to tell me why it fails to actually split the curtain system with grids.