It's been reported, on and off at numerous airports, since TSA started.

I experienced it at IAD in 2002; my brother said "they're making the process as ridiculous as they can so that if another attack does happen, they can ask 'well, do you want us to make it even worse?' " Right theory, but little did he know how much worse it could get.

I can't find the original post from years ago, but someone here described how he asked the second ID checker what was wrong with the first ID checker, less than 10 feet away. Her response was "I naw dem; dey naw me." Brilliant.