You might just change your mind about that if you ever buy a 21 ft Allison !!!!!!!!!!I think that part is cut away because it really isn't doing anything. At least that is my understanding behind it. That front edge of the blade nearest the hub isn't pulling much....most of the pull is in the tips when you are running. That blade area is just extra drag. Cut it out and the prop spins faster. I could be wrong though....
I almost sent my 27" trophy off for an allison cut.....but then after I ran a hydromotive I decided the trophies were best suited for Rangers.