a lot of the replies are insinuating that pack running means slowing down your top runners on purpose in order to form a pack. That would be dumb and I've literally never heard of it being used as a strategy (unless your top runner consistently goes out way way too fast and burns out). Pack running is about pushing from the bottom, and having "less" talented runners run up with more talented ones in order to get dragged along to a faster overall finish time. Now in OP's case with such a large gap between 1 and 5, its not viable for the last few guys on varsity to try and run up with their number one guys, and on every team this sort of thing varries. But more often than not you will have runners who aren't too far off from others (lets say a 20 second gap per runner). It would not be unreasonable to have guys run above themselves at the start in order to find a break through race. A lot of runners, especially beginner/high school athletes are far more capable than they actually realize and can put themselves in a box. It also creates a sense of urgency for the top runners too, cause if it works, then they're being challenged for their spot on the team incentivizing them to run even faster or to finish even stronger in order to keep their position over their teammates.