When would it be appropriate to start a project with the proxy pattern?

For the proxy pattern, we have:

• An interface (or abstract class)


• A subject that implements the interface and does the work


• A proxy that implements the interface and delegates the work


• The client gets an object (either the proxy or the subject) that implements the interface

If you want to modify existing code, it makes sense (to me). For example, say I have clients that use the subject. In a future iteration, I want to add a security layer, so I pass the client a proxy that does the security checks before delegating the rest of the work to the subject.

Is there a scenario where you would want to start a project using the proxy pattern? It doesn't feel like anything is gained if the "proxy" object implements the same interface as the subject. I can give the client an object that delegates the work appropriately, and not be forced to implement the "proxy" with the same methods as my subjects.