Why can't a traditional bow be played with three fingers?

Not suitable. The traditional bow emphasizes thumb play, while the mainstream uses thumb. Three-finger play may be suitable for some specific bows, such as Turkish bow, but it is not suitable for traditional bows. Moreover, when the three-finger play is unfolded, the strings naturally rebound from the inside, which is easy to pull the face. Moreover, the three-finger play is not friendly to the short bow, and the deformation of the bow arm will be exaggerated when the bow is full, and the rebound is inconsistent, which is not good for the bow. Therefore, the traditional bow can't use the three-finger bullet, because it is not suitable for the traditional bow.