What is the use of Shared State property

The broker administrator guide(7-1_Broker_Administrators_Guide) states that “The shared-state property enables multiple clients to connect to the Broker using the same client state object. (Typically, a client application does this to enable multiple client processes to retreive and process documents from the client’s queue, there by improving performance.)”

But its my understanding that if two Integration Servers that are not even clustered use the same client prefix that itself would enable both the clients to retrieve and process documents from the client’s queue.So i am failing to understand what can enabling the shared property achieve which cannot be achieved by merely using the same client prefix for the integration servers.

IS creates broker clients with the shared-state enabled. That’s what makes having 2 IS instances with the same prefix connect to the Broker work. If shared-state was not enabled, the second IS instance to connect would not be allowed to do so.