Last week's episode of 30 Rock could really have come out at any point in the show's continuity. Sure, it agreed that the events from previous episodes happened, but there wasn't really any sort of play or acknowledgment of the show's past. The show has always been somewhat ambiguous with its own continuity, able to deal with multiple-episode plots but never really willing to let its characters grow or change. They're stuck at a permanent point, even if the show makes some concessions to plotlines.
This makes âInto the Crevasse a bit odd. The entire episode is based upon what has happened before it, though nothing that was in last week's premiere. If last week's episode was a good, though not great, representation of what the show is in order to attract new viewers, this later episode seems geared towards the realization that at this point no one new is going to start with the show from season four. There's not even an explanation of what that's a dealbreaker is all about, which plays a large part in the episode's development and gives it a lot of its better jokes.