It’s common knowledge in golf that consistency is the most important. It is possible to play to a good standard if you knew your slice was exactly 40yards. The problem is a persons’ intrinsic biomechanics can change on a daily basis due to lifestyle factors. What this means for the golfer is, what will feel like a 5-yard draw swing one day will be and a hook or a fade the next. This is due to the change in functional length of different muscles and nerves and the mobility in the players’ joints, which will give you the feeling that they are swinging the same but they are not. Swing path can be changed by muscles locking the sacroiliac joint on that day or a tight infraspinatus in the left shoulder making the clubface close early.
The most repeatable biomechanical position is neutral and consistent intrinsic biomechanics will mean a consistent golf swing.
Distance, Speed and Power
To hit the ball far you need good impact conditions, that much is obvious. You need to be able to get your body into the correct position for an efficient transfer of energy, converting clubhead speed into ball speed. The less the angle of the face of the club differs from the club path and angle of attack, the more efficient this transfer will be. This is why the smash factor of a wedge is significantly lower than that of a driver. Although we do need a little spin on the ball to take advantage of the Magnus effect, which is another story for another day.
As previously mentioned, if we have more consistent biomechanics then we will have a more consistent swing, and a more consistent swing means we will hit the club out of the middle more often. Increased average distance already. Adding length to your longest drive just through improving your biomechanics is also going to happen. Removing muscles spasms will increase the contractile potential of your muscles, mobilising joints will give you a better range to accelerate through and improving the function of your peripheral nerves (Sciatic nerve, median nerve etc) will also increase your clubhead speed.