Tell what's-his-face to take a flying leap.
If you get an airline used to you, have an ffn, buy tickets on their website, that airline participates in the program, etc -- you'll usually make out.
With another (newish to you) airline you will have to stick your ktn in the field. Getting a Known Traveler Number is another discussion, but it'd show up with a google.
Computers being computers, sometimes you've thought all the boxes were checked, but it doesn't pop up for a particular flight. There's a way to remedy it, but I've never thought it was worth the bother for the odd flight.
The above applies to international outbound flights as well. Obviously TSA doesn't operate in other nations so it's a no-go coming back. The time-saver inbound is Global Entry.