Tile entities (or block entities as called by MCServer) are blocks with extra data within them like chests or note blocks. In vanilla minecraft you can't move them, so I have no idea how the client would respond to it.
I also have no idea what would happen if you would send a block entity to the client but it's a cobblestone block. I don't even know if it is possible.
The client does not decide if a block is an tile entity. The server decides it and then sends it to the client. You can see this when you use cBlockArea to place a chest. When placed you can't open the chest because cBlockArea doesn't support tile entities yet.
(Please correct me if I'm wrong.)
I also have no idea what would happen if you would send a block entity to the client but it's a cobblestone block. I don't even know if it is possible.
The client does not decide if a block is an tile entity. The server decides it and then sends it to the client. You can see this when you use cBlockArea to place a chest. When placed you can't open the chest because cBlockArea doesn't support tile entities yet.
(Please correct me if I'm wrong.)