I don't think hltv works anymore. Nobody uses it since ESL took out cs 1.6 out of their list.
I think you are mistaking the client side hltv tool that provides demos with the stream-like tool that esl used to provide to join a live game and spectate it , every dedicated server has an hltv , its like a command prompt or a non graphical version of the game where you join in and it automatically records everything in game.
OT: this idea was always suggested , but the highstaff always denied it , maybe it has an impact on lag , it is a great idea if it doesn't affect the gameplay and causes lag !