IIRC, when he was carrying 2 big headed drivers, one of them was a 46", 6 or 6.5* loft. So, 8.5* sounds right for this frankenwood.
Wouldn't the whole idea be to strategically meet the Muirfield conditions of long ball roll-outs, due to F&F? Does Phil forgoe the driver on soft FW courses? I don't know and haven't followed it that close.
I would agree with Lynn if he is saying one reason he doesn't like the big headed drivers due to the look of a clumsey elephant foot at the end of a stick. Me too...