I have to say that video is astounding; never heard of anything like it related to TAR ever. Although with my hearing, I couldn't understand a thing Christie and Colin said, it did show what happens with production after the end of a leg interviewing the Racers for edited in commentary in episodes; a process that has been described by endless Racers over the seasons, but never seen until now.
And I get the impression at the end of Colin and Christie's interview segment that some of the production folks might have been around for a long time. (If you watched you'll know what I am referring to.)