I agree, it is not a "rookie" mistake to get dropped. In facts, it is a rookie mistake to fight getting dropped when your fitness level just is not up to the pace. I have seen riders push themselves so hard on fast rides that they cease to really be fully aware of their surroundings. I have seen a number of crashes caused by this. Ride within yourself. Of course, hanging with a fast group as long as you can is fun and it is great training. But it is also important to know when to let them go.