I'm not sure if I understood you, but I think you misunderstood him laugh
A pointer is only valid on your machine. It points to a place in your memory. On another machine it has a different value (points to a different entity, or if you're !lucky! to the same entity).
Instead, identify your entities by client_id and other custom ID methods...


Extensive Multiplayer tutorial:
http://mesetts.com/index.php?page=201