Sir. Pouncealot was not something that was included in the script.
In fact, what Nathan was supposed to say in that scene was 'Hey buddy! How'd you get up there?'.
Yet, Xavier, upon checking the shot to ensure it came out perfectly, simply stated;
"Alright. We're moving on to the next set on the college grounds."
"Let's be ready in ten." he employed a light, rolling gesture of his finger to signal to the rest of the crew who gave curt professional nods as the cinematographers worked to unmount the cameras in quiet efficiency.
"Oh and Kyle. Nice touch with the cat." he casually added as the young star and Jeff, slowly got off the dining chairs.
In response, Kyle gave a light salute with a thin smile on his lips, after which he then promptly turned around and walked up the stairs to gesture to Sir. Pouncealot to come down.