I am not going to say it never happens but purposely induced delays are very rare. You have to remember that Twitch is a community and the people watching communicate with the streamer through chat. Getting a response to something you say in chat 5 minutes later is not a workable solution.

Now, this works fine for large broadcasts where there is no two way communication between a streamer and their followers or in some type of competitive situations, but that is not the norm.