Typhoon It could be. I did build it at 45" and I have ALWAYS struggled with drivers over 44.5". I did try adding some headweight and choking down, but the results were still mixed. I have been struggling with my woods in general as even my 3 wood has been iffy. It's typical for me to start hitting my irons really well and then the woods are useless so nothing new.
I hit the range the other day and I was straighter with my Rogue which is 44.5" so maybe I should just match the G400 to the Rogue with respect to length and weight,