According to Don Zutz, the purpose of a beaver tail forend is compatibility with a pistol grip and keep the hands in alignment.
Just one of many stupid things that Zutz wrote. A classic purveyor of misconceptions. How he ever came to be a "recognized authority" is one of the mysteries of the cosmos.
And Rocketman - once the gun is mounted the grip hand carries no weight at all. If you mount a gun and let go with the grip hand you will see - no change in the weight in the other hand. The grip hand has a number of duties but carrying any weight ain't one of 'em.
And shooting styles change as biometric/ergonomic data is incorporated into sports. You can shoot any way you like, or you can use your brain first and optimize that activity. You chose.
have another day
Dr.WtS