Friday afternoon, (5/13) at checkpoint 3 there was a TSA trying to hurry up people moving though the PreC line. She kept telling passengers to check their boarding passes, if it is not marked PreC they will not be allowed through. They actually did that! For some odd reason there were lots of people attempting to go through PreC without being PreC. There was one whole group of about 25 young men (a tour or a team?) were sent back out and several couples as well as a bunch individuals were turned away. I had never seen that, and was amazed at how many were being turned away. They obviously needed to have a lane checker at the beginning of the line, not sure why they did not. The general screening lines were long, but still within the stanchions.