There's some good literature on the science of racing - you need to read some of that.
You're really asking the wrong question. What you really should be focusing on is the perfect race, which for 6.5k and all things being equal (wind, hills, footing, etc..) is probably slightly fast but not too fast 1st mile, nearly even splits over the next 2 miles and slightly faster last mile+ with a kick. If that race plan puts you out with the lead pack, so be it. There will probably be runners in the lead pack with a similar race plan, and if you're overextending early on to stay with them you'll never beat them anyway. Plus, I think the science shows that going too fast too early and fading is almost always slower than the plan I just described (plus it hurts a lot more). Based on your workouts and good knowledge of the course, you and your coach should be able to put a good plan together.
I know in swimming for a longer race (200M and up), we really look to keep the swimmer close to an even split. If they're fitness level is high, that usually means they've found the optimum mix of both energy systems for that particular distance. And hitting that target can be a very fine line, so race specific training is critical.