Cross-Server Communication

I have tested the cross server communication. What I wanted to happen was to render a project on a server accessible from another server. But what happened was quite different. I had project P1 on server S1 and project P2 on server S2. Now I could open P2 from S1, create a work item W in P2. Unfortunately W is only visible from S1 while it is completely non-existent when I open P2 from S2.

Is this a normal behaviour and if, what is cross server communication made for?