“What such a man needs is not courage but nerve control, cool-headedness. This he can only get by practice.”
Talking isn’t enough.
Learning isn’t enough.
Planning isn’t enough.
All of these things are exceptionally valuable but none of them can completely prepare you for a moment when all the plans go sideways and you have been punched in the mouth. The only way to know how one will handle this is to get in the ring and fight.
If you want to stay calm when it matters you have to practice like it matters because it does…