The Berger range of "marginal" is wider than any other I have seen. I expect it is because they are trying to allow for people to go into colder conditions, or maybe for some lots of bullets to be longer than average. But several authorities from Harold Vaughn to Don Miller put stability...
Racing to finish load development with a new rifle just before an expensive hunt or an important match is a time-honored shooting sports tradition. Best of luck with it!
In MOST rifles the Berger VLD's shoot best jammed, but it's not universally true. This article by Berger's Eric Stecker explains it. They used to recommend jamming all VLD's and just accepted that some rifles couldn't shoot them. But feedback from customers told them there were many of those...
The G7 reference projectile is a boattail shape with 10 caliber radius tangent ogive. This shape is simply closer to the bullet shapes most people use these days (though the G5 is closer for `68 grain SMK") than the old G1 reference projectile (flat base and paltry 2 caliber tangent ogive)...