Originally Posted by
kennycrudup
They have been? What's the Magic Phrase, as I've tried twice (there's a PP lounge in D, too) and haven't gotten anywhere

Use the C gate security line that's left of the D gate lines above baggage claim. DO NOT use the C gate security by the Southwest check-in counters. After going through security make your way to the D gate area (which is next to D gate Pre-check).
On return, go to the D gate security area to get access to the C gates. Pretend to be drunk/stupid. Vegas is used to drunk/stupid, it is how we all make a living - directly or indirectly.