I never check bags, so my interaction with frontline staff is limited to a smile and a "thank you" when they scan my boarding pass.

That said, I find the ATL TSA process just absolutely demoralizing. Every time I fly, the queue is different, lining up this way or that way. Some days, they'll open stanchions and people who came into line after you are now suddenly teleported to the front of the line while you are standing there, dumbfounded. Some days, blue north side pre-check is closed. International Terminal F Pre-Check has odd hours. Some days, the line bottleneck is at the BP scanner desk. Some days, the bottleneck is waiting for a gray tub. Some days, its waiting for the TSA officer to push your gray tub into the x-ray scanner. Never really knowing which line (even normal security) is moving the fastest, because the landside area is so huge you can't visually see all of it. I'm willing to take off my shoes again if the time spent waiting in line was cut in half, but you have no way of knowing when you get into the line. Every day at ATL, its YMMV as far as the experience.