I flew out of "D" on Monday morning (6.20 am); it wasn't that bad. The line was long, but it moves. I think it took me a total of 15-20 minutes, maybe less, from the time i got in the line until I was waiting for the shuttle to D. The way LAS is designed, you can clear "D" passengers thru the "C" security or use the "C" detectors, but you can't do it with A and B. I find the TSA at LAS to be no better or worse than at most busy airports....always barking orders, seeming to hate their jobs, etc. but in general, the lines do move fairly speedily.