Send the text to all the people observing a game but NOT the players
of that game. The game used is the primary game you're observing, or
else the game you're playing.
Observers with "kibitz" variable off (see help vars) will not receive the
message, neither will players censoring you. You can use whisper if you are
registered and are observing a game, or if you are playing a game. If you
want to comment on a game, you should use "kibitz" or "whisper" instead of
"shout". Upon completion, whisper will print the number of people who
received your message.
If you are observing more than one game, use the "primary" command to
choose which game your whispers will go to. Or you can use the "whisperto"
command. For example, "whisperto 136 Good move." sends your comment to
game 136.