I personally believe that length adds up quicker since you only measure mass in certain spots on an antler.  Now if you have both length and mass you have a booner. 

I have only scored two deer but everything I have read about it does indicate that mass has the least affect on the score. The biggest thing would be the length itself and all the width measurements. The tine length is huge along with the depth of the front forks, on a muley anyway. I have a 27 inch 3 point buck that scores almost nothing since the forks are crab claws and on opposite sides. On the other hand I have a 22 inch 4 point with brow tines and even forks and average mass that net scores at 168.

Again that's all I know about it but there are a lot of things that affect the score.

For whitetail its the 40-30-20-10 rule. 40% is tine length, 30% is main beam length, 20% is mass measurements and 10% is width. There are exceptions to the rule, but if you score alot of whitetails, it comes out pretty close.

Mule deer, I would think come close to this same rule. I haven't scored a lot of mulies, but just by studying their racks and how B&C scores them, it should be close to this.

On elk, from what I have read and practiced, the biggest contributor is tine length. You have 5 points on each side (6x6 6th point is main beam) and they each average 14", you have a 140" of score already. Then the main beam length, if each one is 45" long, you have 90" of score. You move to mass and you get 4 measurements on each side and the average is 7" you've got another 56" of score. Average spread is 42" or so, that would leave you with a gross B&C score of 328" You might run into a bull that has a 60" spread or might have 80" of mass, but I think even in elk the 40-30-20-10 rule will get you in the ballpark if you put your imphasis on tines, then main beams, then mass then width.

Yeah, it kills me here in Texas how many of my buddies, when I am describing a buck, the first thing out of their mouth is "HOW WIDE WAS HE?" Everytime they ask me how wide the deer was, I always tell them something really small like 12-13", but his TINES WERE HUGE. Someday maybe, width won't matter so much, although it sure does add to the beauty of the rack.

I know length adds up quick but here where i hunt they have lot of deer with heavy mass.  so it all depends where you hunt.  But don't get me wrong i love both!!