I'm not sure if it's a TSA or airport rule, but several airports have done this to me, including SAN. If your airlines does not fly out of the terminal in question, this may happen to you.
The best thing to do when jumping offline is call and list yourself, and then print a security document at a kiosk or pick one up at the ticket counter.
One time I was jumping on a company that used carbon-copy JS passes...I had a few blanks in my flight bag so when TSA stopped me, I whipped one out, filled in the date, flight, and my name right in front of them and THEN they let me through
