Hers's how it works.
The Clear or PT customer provides a bunch of information for a TSA background check, along with verifiable identification. A birth certificate or passport are the only primary IDs they accept, along with some official photo ID.
After you sign up on line, you print out a form and go to the enrollment counter at the airport that has the service. They scan your irises and all fingertips. The data is then sent to Clear and burned to a chip on a smart card. The chip has the biometrics data and the necessary keys. The second issue of cards had a photo on them as well (the originals didn't).
When you arrive at the Clear/PT gate, you show your boarding pass and inset your card into the reader. (The PT folks a Jacksonville would usually take the card and insert it after checking the photo. The Clear folks at Reagan always asked the customer to insert the card). When prompted, you placed a finger on the reader, the system scanned it, read the chip, verified you and you were on the way. If the finger scanner couldn't get a good read, they'd scan the iris instead.
Once you're done, you proceed through the line.
I've read some comments here about the service at some airports, but my experiences have always been very positive. The Clear employees at Reagan couldn't have been more polite and helpful, and the early morning lady at the PT line in Jacksonville got to know me on a first-name basis.
As for the advantages of the service, yes, you do have to do the shoes/metal/laptop bit and step through whatever scanner they use. You have to do the same things as everyone else in the other lines. But you don't have the wait as you make the turtle crawl through those lines with the families and their obnoxious kids or the irregular travelers who haven't figured out the rules yet (despite the presence of shouting TSA agents telling them what to do).
Call me an elitist, but I travel a lot, usually when I'm pretty tired, and considering the lack of fun in getting on and off planes, the faster I wade through that shit, the happier I'll be.
I have travel routine. I do certain things *prior* to arriving at the gate (even the airport) that I know will get me to where I'm going faster. I really don't wish to put the brakes on that because of rambunctious children, strollers, and elderly people who decide to save the baggage check fees by carrying *everything* on the plane.
It's bad enough waiting after boarding (or simply trying to get down the aisle while boarding) because some idiot filled up his rollaway suitcase so it's just a little to big to fit in the overhead without forcing it in with a crowbar, while the rest of the boarding passengers line up, waiting for you to clear the aisle.
My big issue is traveling on Monday mornings. I live 45 minutes from the airport, and my departure times are usually between 6:30 and 7:30 AM, depending on the airline. Knowing that my wife and I can stay in bed an extra 30 minutes makes that service worthwhile.
There's also a lot of whining here by the so-called "privacy concerned" regarding what's going to happen to the data, or why the "government" has to use the data, or why the TSA sucks, or whatever.
First of all, as far as the TSA and their work is concerned, it is what it is. I wish it was better, or unnecessary, but there they are, and I need to get through them to get on a plane. So I deal with it. This service helps. I've personally never had an issue with them, my bags, or anything since I started using this service.
Second, the information you provide clear is no more intrusive than the information anyone can retrieve on you for the cost of a background check fee. They ask you name, address, phone number, a few other background details, they ask to see a birth certificate or passport and some kind of official photo ID. I don't recall having to provide any information to them that I would consider particularly intrusive. Hell, I had to give up a LOT more information about myself to get my current security clearance from the DOD.
Third, the information is given voluntarily by me. If someone, like you privacy whiners, doesn't want anyone having this information, don't sign up for service like this. If I'm willing to do this and pay for the privilege of skipping the cattle drive through the security lines, it's my money, right?