By reality distortion, PG has an amazing ability to sell you on a vision. It's often times because he has spend a lot of time thinking about a problem or a solution, and there's no real way to argue back in real-time.
I get the reality-distortion field from Jobs thing, but that was much more specific to his personality. He didn't care whether or not things were possible, he just told people to figure them out.
I'm sure that overlaps with vision casting in some sense, but I would hate to see the word "reality distortion field" pop up all over the place and start being a SV buzzword when people are really just referring to leadership.
In any case, visionary applies just as much.
I'm not unique in this observation, other founders say the same thing.