If you read Underwoods book and if memory serves me, the idea for their veer came from watching the cotton bowl one afternoon.
Good book on the Veer for 11-Man
http://coachyash.com/wp-content/uploads/2013/11/The-Explosive-Veer-Offense-Book-1.pdf
The O'brien veer always started with what Underwood called the "Man Under". He was the initial exchange man. When ran correctly he also became 3rd option in their veer.
The basic veer
1 )Man under received Snap
2) Man under pitches to Half Back (also called the "Read Man" (Initial exchange took place, now I have 3 options, really 4 because passing is always an option), The Man under moves down the line to become the outside pitch (Option 3).
3) Based on initial reaction of the defense the Read Man either hands off to the Dive (Option 1), or he keeps it and moves down the line.
4) Based on the Defenses 2nd reaction, he either, keeps it, and moves up field (Option 2), or he pitches to the to the Man Under who is now on the outside in order to stretch the sweep (Option 3).
5) Or if the whole thing blows up, and by now the offense and defense are so stretched you have option 4, the throw back pass or to someone who has snuck behind the safety from the weak side. Which whoever catches it (Offense and unfortunately and sometimes the Defense) is most likely going to score.