JamesK,
Interesting commentary. Primos team has for years spoken to how one arrow maker they buy from always spines the Easton ACC for the high side, mark it and then fletch the cock feather at that high point and that it has tightened their groups considerably...
Another friend, who made and sold thousands of arrows made from varied shafting, sold out of his booth on the tournament trail, claimed that almost every maker of CARBON arrows has variance in the spine, weight, and straightness of any given dozen shafts. Across the board... he did find ONE mfg that was most consistent lot to lot.
Having found those variances, NOT finding a stiff side where the wraps of material overlap, would surprise the bejabbers out of me...
I never bothered with testing the Griz Sticks when I "torture tested" them years back... as Ed's explanation of how to do it, didn't work for me...Joey's clip, showing the shaft sticking out beyond his cupped hand for balance, makes me want to try again...
Spine testers will reportedly also show if there is a "stiff" side... I don't have one so can't vouch for that.