FWIW, we flew on Southwest yesterday out of Baltimore to San Diego. We got a pre-board due to my wife's knee problems, so we watched everyone get on the airplane from our first-row seat (Southwest has no assigned seats, of course).
My wife saw the TSA guy show his creds to the pilot and head flight attendant, and he sat down in the second row on the aisle. He was dressed like a vacationer or business casual (open neck print shirt, slacks, didn't see the shoes). He conversed with my wife several times on the long flight, and with the lady in the window seat - mainly about weather and vacations. Very pleasant and well-spoken fellow. Seemed to have a laptop and some business papers - couldn't look too carefully, of course.
This is the stupidest thing I've ever heard of.
The Marshals should be undercover. Board with the rest of the passengers, dress like a regular passenger, everything.
The general public is familiar with the concept of undercover cops. We'll accept that the guy is a professional once we see his badge.
I once had the pleasure of seeing an undercover NYPD Transit Officer in action. A really drunk guy on my subway started hassling the other passengers, threatening and shouting. This average looking, kinda scruffy guy stood up, flashed his badge, and took him into custody. He took him off at the next station. Nobody in that car was thinking "boy, does that cop look like a slob."
Homeland Security is also admitting that they're wasting a valuable opportunity by only watching the passengers after they have boarded the plane. A marshall in jeans and a sweatshirt standing around before boarding has an excellent opportunity to scope out the passengers and look for anything suspicious. They could seek out troublemakers, but choose instead to sit back and wait for the terrorists to start something before getting involved.
Dumb. I expect better from Ridge and Co.