There's lots of valid reasons to ys on reserve. If you're a commuter and don't want to have to sit short call in a hotel or crash pad. I ys if I know I'm going to get a trip to pick the better one out of opentime, to put yourself over guarantee, or sometimes you can get an extra day off by ys a 3 day or a 4 day when you have 4 or 5 days availability. You gotta make the best out of reserve and don't understand why people make a big deal out of yellow slipping....