Not by my logic but his own admission : 80 yards at 1.32 secs he states standard shell, I believe he even shoots it beyond that point but changes to 5's at 100 yards. Whatever you like to use as a crutch it doesn't matter, I'm generally only interested in facts, incorruptible numbers and incorruptible evidence. GD CAN reliably break edge on 80 yard clays with 7.5's (certain presentations will prove less reliable) as can many others including Winser and Solomons. If someone is showing you birds beyond that range then using 6.5's is not needed because of a shortage of kinetic energy but merely giving random breaks which you are interpreting as evidence.