Good points, Martin!

The nicer you act, the further you get. This applies to SO much more than TSA: doughnuts at the automobile shop are not germaine to this thread, but have always gotten me through ASAP, with a smile, and perks that are worth at least as much as a box of doughnuts--and into a bay first, the NEXT time I visited. A box of chocolates at Christmas, at the lunch deli, have always gotten me a year's worth of lunches, far and above what I would have expected for the price...

I don't fly often, but did last Spring with a Pre-check ID. I acted dumb ('cause I was), and got through so fast my head spun like a top. I made sure to thank the TSA guys: (they were following their protocols), but were glad to not take grief, because of it.

Going in presenting myself as ignorant of the procedures, ready and willing to cooperate with them, and anxious to fulfill the requirements, has always sped me through the process at the airport.

Learn the clerk's name--if you don't catch it right off, ask the clerk to repeat it--and thank them, by name--at the conclusion of the transaction.

I didn't think of it aforehand, but I guess the whole premise of this post is this: be polite: do you really want to deal with someone who has been ticked off by their previous contact, or do you want to deal with someone who has been validated by their previous contact? We all want to feel as if we are doing something constructive, even if we feel insignificant, because we are constrained by company policy. Complaining to the customer service reps will not solve the problem: complaining two levels up will make the difference in policy change, and mentioning the CSP's name will effect a change at the most basic level...