Weiss asked, so Yang Yi answered.
If it were anything else, any other question, Yang Yi would prefer to keep it to himself; he was accustomed to hiding his true self, in every aspect.
But what Weiss asked about was martial arts, and as one of the few inheritors of Mian Zhang Fist, Yang Yi had the obligation, the responsibility, to reveal the martial art he practiced.
And Weiss was indeed a master of combat, so Yang Yi had to respond.
This was out of respect for Weiss, and even more so, the most fundamental but greatest respect for the martial art he inherited.
Now, Yang Yi had answered, and then he said, "Please enlighten me."
"Please enlighten me" meant that you may now comment on this martial art; if you say this martial art is very impressive, and I'm no match for it, then Yang Yi would modestly demure a few words, and everyone would be happy.