How do virtual properties work with state tracking

[wolfsage]

Right now, virtual properties can be anything. For example, a virtual property could be "is_recent" that compares the creation time of an entity against now() and returns true if created in the last hour or false otherwise.

The problem here is that apparent data on the objects can change value but not change the 'state' of the class of objects.

Say our current state is 0, and we call setFoos/create. Our state becomes 1, and our object has a is_recent of true.

In 2 hours, is_recent is now false, but state is still 0. Now our client and server are out of sync, and if the client says getFooUpdates sinceState => 1, the server will say nothing has changed.

Is this something we can defend against consumers mistakenly doing, or should we minimize these types of issues through the documentation?