The most demanding part of a WRC hearing, if you are acting for a client or even arguing your own case, is listening to the evidence of the opposing witness(es).
There are many parts of the hearing, including your submission and your direct examination of your own client(s), that can be prepared in advance.
But the evidence of the other side’s witnesses must be listened to carefully and any openings for a fruitful, productive line of enquiry, must be ruthlessly avaialed of.
This involves intense listening and preparation of your questions for the cross examination, and the most demanding aspect is you must formulate your questions in real time, as the evidence is being delivered.
The concentration that this requires is exacting and energy sapping.
But when you pull it off with some degree of success, it is tremendously satisfying.