From the book:

  "I saw the battle in there. Not exactly hero-like, but you do show promise. Where 
did you learn to use your blade like that?"
     "In the army," Grover said. "And then, later, in private study with Curouch."
     “Didn’t Curouch accidentally stab himself with his own sword, twice?”
     “I have to go,” Grover said, turning away.
      Ballah grabbed his arm. “As I was saying, my friend, I was scouting for Hudo, but 
saw you instead. You're a natural! The witty banter. The way you retreat to make 
people believe you're a coward. Then allowing yourself to get wounded to fool your 
enemy that you’re inept. That was genius!  I made a killing on my wagers. And the 
tapestry bit at the end was inspired. You really know how to put on a show. What do 
you say to signing a contract? Say, five years? Doing hero work?"