After the performance order of the teams was decided, Kwanghee, G-Dragon, and Taeyang went to the studio and began recording in earnest. At first, Kwanghee was his normal chipper self, happy to be working with the pair. He said, "Are we gonna do choreography now?"
However, after the first recording, G-Dragon repeatedly told Kwanghee, "Let's do it again!" in a serious tone. Realizing that the time for playing around was over for the moment, Kwanghee, probably unconsciously, begins to talk to G-Dragon using honorifics (more formal, polite words generally used for elders or those of higher status).
You can watch the exchange above. Were you surprised by the sudden serious mood?