At 2:37pm I emailed a generic alias I found on the Pittsburgh airport web page. At 2:39pm their public affairs manager called me. He explained how frustrated he was about this process recently, as he's seen the same thing I complained about. He said traffic is up 10% overall but much more than that during peak times. He said they are not allowed to enforce this, nor can the TSA. He said he would like to see all the airlines, who do have to ultimately enforce this, to work together and chip in to hire employees to direct line traffic during peak times. He said this is the arrangement they use for wheelchair runners.

He agreed that the TSA's stance is that they are a government entity and cannot enforce premium airline passenger benefits. I explained that I'm quite sure that MDW and CLE do so just fine, and he's going to contact colleagues at those airports.

As far as how the one first class sign / lane got there in the first place, he thinks the airport put it up in negotiations with the airlines directly. He said they are customers of the airport just like passengers are.

I think I recall earlier threads where Southwest had in fact gotten involved and figured out working arrangements with the TSA. Whether Southwest chips in on extra costs, writes them a thank you letter, or gives one of the managers a few free flights a year as a wink & a handshake deal, it's working at many other places.