Q & A: "Old Saito sequence at the end of the film"
Q12.1) Is this limbo?
Answer: Yes. Most definitely.
Q12.2) Is this related to the “building level”?
Answer: No. See Section 2 for explanation.
Q12.3) Why was Saito so much older than Cobb?
Answer: Two reasons. One, Saito went into limbo before Cobb. Two, since limbo felt like an eternity, time would have moved extremely slow, resulting in the advance ageing in Saito.
Q12.4) Why did Cobb need to save Saito from limbo?
Answer: Cobb did it for a couple of reasons. One, he needed to remind Saito of the arrangement to free him of all criminal charges so that he could return to his children. Two, Saito would have lost sense of what was real. Stuck in a place for decades, limbo had become his reality. If Cobb did not come to tell Saito that he was in limbo before the sedative wore off in reality, Saito would have woken up in reality thinking that that was his dream, and that he should kill himself to wake up from his perceived dream (notice the similar psychological problem with Mal). A dead Saito would not have done any good for Cobb’s future.
Q12.5) Saito picked up the gun on the table and the scene was cut prematurely on purpose. What really happened?
Answer: A few scenarios could have happened. Saito could have shot Cobb and then himself, or he could have shot himself only, or he could have shot Cobb only, or he didn’t shoot anyone. I will explain why the last scenario is the most plausible under the circumstances.
After Cobb revealed to Saito that he was in limbo and that there was an arrangement to be fulfilled back in reality, Saito would then realize that he was in a dream all along. He then picked up the gun, and the next scene showed them waking up in the airplane. Anyone would have inferred that Saito shot Cobb and/or himself. But if you dig deeper, that inference is wrong and can be easily debunked.
The only way to get out of limbo is to wait for the sedative to wear off. One cannot kill himself to get out of limbo, because if it could be done, limbo would not be a frightening prospect anymore as one could escape from it easily. There is also the uncertainty of killing oneself in limbo because it may even cause the person to go into a “deeper limbo” (this “deeper limbo” theory offers an alternative explanation to the film’s ending, which I will elaborate in Section 4).
Saito instinctively picked up the gun because he thought limbo was just another dream and that he could return to reality by shooting himself. What we didn’t see was Cobb intervening by warning Saito that even if he shot himself, he would not be able to escape limbo, and that the only way out was to wait for the sedative to wear off in reality. So I propose that Saito did not shoot anyone, and both of them waited.
**There is another argument that when Saito picked up the gun and was about to shoot both himself and Cobb, the sedative coincidentally wore off, thus accounting for the immediate cut to the airplane.
Remember that the team (Arthur, Ariadne, Eames, Yusuf, Fischer) was still waiting at the “van level” for the sedative to wear off? The dream machine was programmed to administer the sedative for the bulk of the flight time in reality, which was about ten hours. This would give one week at the “van level”, meaning that the team had to wait at the “van level” for one week before they could wake up in reality. One week would probably give decades in limbo. Therefore, the coincidental wearing off of the sedative might be too prompt and convenient to happen.
Comments
That aside, your explanation makes sense. Though it must be argued that when Mal and Cobb were exploring the dream world, they were unlikely to have used a sedative, and thus when the train hits them, they wake up in reality, "escaping limbo by death".
But for Cobb and Old Saito's case, a strong sedative is used, so "escaping limbo by death" may not be certain as the sedative may not have worn off yet. Hence, shooting themselves would only result in going into a deeper limbo, which doesn't make their situation any better.
What do you think? =)