Wise advice. I stopped using my (UK) passport when secondaries were in fashion at boarding gates. I was at LAX, early for my flight, and noticed that all those headed for LAS showing foreign passports were selected for secondaries while those showing D/Ls walked through. The furriners were mainly EU citizens.

I started using my US PortPASS (photo, dob, PP no on front, chevron info on back) but this is now expired, so I generally use my Swiss ID card (5 languages and chevron info) but at least it has a photo and dob so must be OK.

I'd like to use my London Oyster card (self-laminated photo and handwritten name) but won't as it doesn't confer public transportation rights in the US. It worked in Mexico when I refused to let the security person retain my passport when visiting a Government building. English language and photo, must be OK. Pointless, really.