To all the naysayers,
There is a pretty strong correlation between the viability of training groups and the viability of pack running.
Our 1-2 girls, our 3-4 girls, and our 5-7 girls all train together, and we encourage and expect them to cue off of their partner during their races. 1-2 usually go out behind the leaders and make a surge to the lead before the mile mark. Our 2 in particular would get herself in trouble early trusting her own feeling, and it's easier to get her to relax and be patient early knowing the other girl holding back is the likely favorite. We have a freshman girl at 5, and it is a help for her to shadow our 6 when navigating larger invitational fields. She is becoming more comfortable at finding the point in the race where she can surge ahead, but it takes a lot of the uncertainty out of the equation when a strong, consistent runner can basically act as your early pacemaker. 3-4 have the best internal sense of pace and effort and will run more independently, but our 4 always has a vantage point on 3 and her movement up the field to be sure she's responding at appropriate times.
On the guys' side, our top four run virtually every training session together, and they race their best when they are in a tight group (within two seconds) for the first 2+ miles. Whoever is having a good day can keep the pace pressed down in the middle mile; whoever is hurting can tuck in like a marathoner and try to hang with guys they've hung with dozens of times before.
The point is not to artificially slow kids down, but to help them navigate the much messier racing field (compared to track) of the XC season.