This is a question concerning the time Christine, Elijah, and Ulysses spent at the Big Empty. Did this take place before we were shot or after? Johnson Nash explains to you; "I told him, sure as lack of rain you were still kickin'", given how surprised Ulysses was to see your name on the list with the other couriers at the Mojave Express. Why is it that he talks to Christine on those audio logs as if he knows that already, and is hell bent to have you meet him at the Divide? That would mean his time there at the Big Empty was right after you were shot, right? But one could easily start Old World Blues, Dead Money, or any of them at level 1 and pretty much screw up this assumption. Might be a design over thought. But I'd like to see what you all think. Maybe a dev can chime in?

well there's no specific references, but in the last patient log in OWB Ulysses talks almost as if he's seeking revenge against courier six, if you take those events as being before the start of New Vegas proper than what Nash tells you would mean something like "Ulysses was planning on a direct confrontation but saw six's name on the job list and knew that he/she wouldn't be able to survive it"