The TSA has been experimenting with a setup that lets passengers self-sort into separate “expert traveler” screening lanes for travelers who are fluent in TSA procedures. If you don’t want to be rushed or need more time you can choose the slower “family” lane instead. Some airports also have an intermediate “frequent traveler” category.

The screening procedures are identical for all lanes; the theory is just that expert travelers will follow those procedures more efficiently. I’ve been caught behind idiots who don’t understand that keys are made of metal or that the rest of us took off our shoes for a reason, so I appreciate the potential value of this segregation. Moreover, I applaud the broader effort to try new ideas to smooth out the complex screening process.

In practice, however, this idea fails completely. I just saw it in action at DIA – one of a few airports in the pilot program – and it just didn’t work.

I saw only two lanes designated for the “family” category when I went through, yet both were completely empty – not a single person was in either line. All the remaining lines were designated “expert traveler” and were clogged seven or eight people deep. I forfeited my (deserved) “expert” title and breezed through the family lane without missing a step.

In one sense this was a fluke. Surely at other times the family lane has at least a few people in it, and one uncoordinated parent with a disobedient young child could shift the entire balance. However, it highlights fundamental underlying problems.

First, lots of people want to believe they’re experts when they’re really not. And even genuine experts can make mistakes. Normally I fly through security in a smooth anti-terrorism ballet. Then came the mishap a couple months ago when I waltzed right through still wearing my cell phone and keys. Sorry, folks. I just held up the line. I know keys are metal, I swear!

More importantly, the total wait time in the entire system is exactly the same; it’s just being redistributed. The slowpoke who takes five minutes to sort luggage and remove liquids will still take five minutes, he’ll just be holding up a different line. The assumption is that slow people will be more tolerant of other slow people.

The same theory went into the Box Office Babies program at the Coolidge Corner Theatre in Brookline. Parents can bring their babies to the movies and let them cry as much as they want. Crying babies in these screenings are no less disruptive than in any other screenings; they’re just disrupting other people who happen to have babies themselves.  Some parents would still prefer to watch the movie uninterrupted, so they opt not to go to Box Office Babies (and presumably wait for the movie to be out on DVD).

At airports we don’t have the option of just bypassing the security line (perhaps a door marked “No Criminals Allowed” would work?), but some inexperienced travelers will still want to stand on the shoulders of experts before them and breeze through what was (until then) the fast lane.

Finally, this idea solves a problem many airports have already solved by just ushering those who fail the screening for any reason into a separate line to try again. A know-nothing novice with bottled water in his backpack and a knife in his pocket gets brushed aside, as does a seasoned guru who just forgot to empty his pockets this trip.

This system has TSA officials doing the sorting, so there’s no chance of someone being in the “wrong” line. And this way travelers don’t have to learn yet another policy on their way through the security maze. For me, choosing which type of line to join added a second or two of decision-making time, when I’d normally just glance around and hop into the shortest one.  (It doesn’t help that the “black diamond / blue square / green circle” designations, so obvious to those who ski, meant absolutely nothing to me until I read more about it.)

We should welcome new ideas from the TSA even when they don’t work out, but let’s scrap this one before it’s too late and we have to listen to a New Yorker with no luggage mouthing off to the foreigner in front of him who won’t take off his chain mail in the black diamond lane.