Had a similar experience this past Wednesday at T-3 connection area Fast Track. Except the problem wasn't a long line, there were only about 8 people in front of me. What held up the line was one woman who spent over 10 minutes digging through her luggage for toiletries, etc.

Finally an agent came up behind us, pulled back the barrier and redirected us to the regular line. The fumbling lady at the front of the line was just getting to the scanner as we exited the regular line.