With some forehands, the hitting side of the stringbed faces almost the backfence during or at the end of the take back( Sock being the extreme ). It's usually the semiwesterns, full westerns but there are exceptions like Murray and Ferrer where it mostly faces down the court. Even though I have been using Semiwestern lately mine never faces the backfence but rather looks like an eastern take back. After watching the video and comparing with others I noticed that I automatically supinate my forearm during the take back, almost like an instinct to keep the hitting face of the racket relatively towards the ball. Now the question is how significant is this? What comes to mind is when the forearm is in pronated position like Kachanov's, it flips/travels more at the beginning of the forward swing and adds to racket head speed. Thoughts?