Messages and commands are nearly identical: they both have a name,

they can both have parameters stashed in a table, and they both play
stuff out of the actor command list.  Merge them; now the only
difference between playing and broadcasting a command is that playing
plays recursively on a tree and broadcasting sends to all subscribers.

The distinction between "messages" and "commands" is cosmetic now;
everything is a message.  The only thing special about commands intended
to be received as a broadcast is the "Message" suffix, which subscribes it.

stepmania/src/ScoreDisplayCalories.cpp

@@ -49,14 +49,14 @@ void ScoreDisplayCalories::Update( float fDelta )
 	RollingNumbers::Update( fDelta );
 }
 
-void ScoreDisplayCalories::PlayCommand( const RString &sCommandName, const LuaReference *pParamTable )
+void ScoreDisplayCalories::HandleMessage( const Message &msg )
 {
-	if( sCommandName == m_sMessageOnStep )
+	if( msg.GetName() == m_sMessageOnStep )
 	{
 		UpdateNumber();
 	}
 	
-	RollingNumbers::PlayCommand( sCommandName, pParamTable );
+	RollingNumbers::HandleMessage( msg );
 }
 
 void ScoreDisplayCalories::UpdateNumber()