The actor who plays Tim giving a side interview about the actor who plays David (who is his real-life boss) while recounting how he wasted a work day by messing around, while also joking to the camera with dead-pan delivery, immediately followed up by a clip of the boss wasting time recorded by the same camera crew who recorded The Office, is all just WAY too meta for my mind to take in.
There's no real joke as such, it's that Gervais would constantly ad-lib extra little bits of dialogue to make the other actors crack up, ie riffing on Tim's last name which totally broke Martin Freeman. RU-vid deaf knobby burton for more of this, except there it's Gervais cracking HIMSELF up and ruining a take. Over and over.
@@MearnieToon it's set in the early 2000s, also Gervais and Merchant intentionally made the show look washed out and depressing and the clothing was made to reflect that.