The other issue is that it can take weeks of study to even reach a minimal level of fluency in Morse. 5 WPM is the basic metric. You could tap faster with much more practice, but the proctor would almost certainly notice the student furiously tapping patterns onto their desk with their pencil.
To review you need to devote weeks of study to learn an encoding that is poorly suited for the task, and that has a very slow transmission rate so that you can transmit a message that everyone in the room might be able to hear?
