I used to do public debate. It was extemporaneous which meant you were given a topic 10 minutes in advance and told what side you have to argue. Even with one subject and position that shit is hard. I can't imagine going an entire event live having to adlib so much and not being able to prep interviews and just getting your facts right all night let alone trying to be personable and entertaining.
I laugh at mistakes too but just saying, it is almost impossible not to make some, even if you knew the right thing to say. What he is good at, which is hard to teach, is keeping it seamless and not letting a mistake throw him off. A lot of people were indifferent to him when he started but look at the improvement already. I think he may end up being one of the best. JMO