The intention with regards to properties was never all that clear to me from the documentation, to be honest.
I *thought* that each subgraph would have a local copy of all properties (as they were at subgraph creation time) and the modifying these would not change the properties of the corresponding global vertex/edge, and my code actually relies on this.
Am I going to have to change my code design, either to accommodate the current design or a future fix?
Me neither. This is really my first time digging into subgraph. It makes sense (to me) that each vertex/edge should have only one property, but I can see reasons for localizing properties as well. If both are needed, I can create specializations of property_map that select local/global lookup strategies. Would that be acceptable?