I Have Used The Pbs With All My Students At Different Points Of Talent. The Ones That Do Not Like The Pbs Cannot Keep A Constant Pressure To Follow Through. I Continue Until Those Fellows Understand The Constant Flow Of Force And Not A Thrash. I Also Use The Pbs In Conjuntion With The Sheriff To Both Feel Pressure And Aim In 3 Dimensions In Putting. The Object Of The Pbs Is To Magnify The Secret And That Is Not Easy.