Precheck except sometimes
 

I have a NEXUS card which gives me a known traveller number. Usually
I get precheck on my boarding pass, but sometimes I don't, and I can't
figure out what the difference is. TSA vaguely claims random
something but I don't believe them.

On a recent trip, I intended to fly ITH-EWR-FLL / DFW-EWR-ITH, with a
FLL-DAL leg on another airline. I got precheck on the first and
FLL-DAL but not on the last one, which was a surprise since I never
precheck on one leg of a trip but not another. I suspect the problem
was that due to airline screwups, we drove to EWR so I called them to
delete ITH-EWR which they did (their problem, plane was two hours late
on a 50 minute trip.) So when I checked in for the return, I had to
call them to do something to the ticket to allow me to check in. That
probably made it look like a last minute purchase. But it was still a
pain.

Bonus mystery, my wife flew ITH-EWR-FLL / FLL-EWR-(ITH), same deal, got
precheck on everything even though she never signed up for anything.

Precheck except sometimes
 

In John Levine wrote:

I have a NEXUS card which gives me a known traveller number. Usually
I get precheck on my boarding pass, but sometimes I don't, and I can't
figure out what the difference is. TSA vaguely claims random
something but I don't believe them.

It's supposed to random, to keep the bad guys from figuring out the system.
So they say.

On our last flight from MSP to ORF, before my wife and I got our numbers, I
"randomly" got "TSA PRECHECK" on my outbound boarding pass, and we both
"randomly" got it on our return flight.

The reduced hassle at security was enough to convince us to sign up.

--
St. Paul, MN