I guess arbitrary isn't the right word but... What do they really measure??? Bone... Does a bigger rack mean it's the most dominant animal in the woods?
Here's my point... A couple of years ago I saw one of the most beautiful 8 point mounts I've ever seen... Damn that rack had mass... It gross B&C scored in the upper 160's... Add a tine on each side and that buck makes the books... But I can just about guarantee you that buck was as dominant as any in the region.
Maybe some of us take measuring "bone" a little to seriously... Not to be accusatory... I would love to shoot a book buck as much as the next guy, but the rack is really just measuring one element of a mature buck.