'SSSSSS' can be a bit silly... last week, for automotive reasons, I was obliged to pax it - United, EWR-BUF via IAD.
Male, foreign, last-minute booking with a 3rd-party credit card, one-way, travelling alone.
Wasn't entirely surprised to have 'SSSSSS' all over my boarding pass at EWR.
Was somewhat surprised to leave the secure area during my IAD stopover, and on returning through security notice that my boarding pass for the IAD-BUF sector did *not* have 'SSSSSS' on it - just went through normal screening.
If I was 'risky' enough to merit 'SSSSSS' at initial embarkation, surely it's a bit of a hole to not have me 'SSSSSS' at stops en-route? - I could have picked up *anything* whilst outside the secure zone at IAD...
Silly.
R1