If he's not going to read that little bit of text, he's going to be really screwed when he starts Dead Money and finds out that people who don't pay attention to such things tend to die messily in that area, no?
Most likely yes.
The Elijah introduction dialogue
is after all kinda long, some people might just want to "start it already" and try to skim through it barely paying attention. (I wonder how well they'd do in games like Baldurs Gate, Icewind Dale, Planescape and Fallout 1 and 2...)
But then again, it's their own fault for doing so.
Fallout is after all an RPG first and FPS second. (Well, with FO3 it's sorta 50/50 if not 60/40 with the FPS part.)
I didn't pay attention to Vera's final message and clicked the second one and was like "Okay.. I must have done something wrong or this DLC is pure crap."
Then I reloaded, payed attention to it, didn't click the one meant for Dean and voila, completed it with a smile on my face.
Until I found out I couldn't return.
Then my blood started boiling again.
Then I calmed down.
Then I ate a sandwich.
It was good.
It had cheese, turkey and some pickles on it.
Drank some milk with it as well.
Then I started the DLC again with another character.

Aaaanyway... metalthrashhinken, LISTEN to what Elijah says in the introduction dialogue.