Following the last post on the dip and drive portion of the jerk, let’s get into the spit jerk technique, starting with textbook foot position.
In the receiving position it's important that both feet split the same distance in opposite direction. This ensures equal distribution of the weight overhead to both legs, resulting in a balanced jerk, at least in the sagittal plane. The distance of the split will be predicted by the tibia being perpendicular to the platform. The distance of the split will vary because each lifter’s femur length is different, but the front foot should ultimately move forwards far enough that the tibia will be perpendicular to the platform — if not slightly further forward.
The width of the split will depend on the stance of the dip and drive position, optimally the split stance will be slightly wider than hip-width apart. This usually equates to the feet moving one foot-width laterally in the split. Meaning that the split is actually a diagonal movement. The heel of the back foot will be raised leaving only the ball of the foot on the platform and pushing in a posterolateral direction, while the whole of the front foot is planted fully on the platform, pushing in an anterolateral direction.
To ensure a vertical torso inclination angle the back leg should be slightly bent. With the back leg straight the lumbar spine is likely to compensate by extending, resulting in a weak position due to the decrease in intra-abdominal pressure. I say “likely” because it doesn’t always compensate, however, in most cases, it will compensate. Additionally, the bent knee will make it easier to adjust the depth necessary to receive the bar overhead — especially for people with longer limbs.
In regards to the overhead position, ensuring that the elbows lock out simultaneous to the feet hitting the platform is huge. As soon as the feet hit the platform the bar will start descending, and if the arms are not locked out at that point it will either end with a press out or, worse, slip out of the hands and decapitate you… So I'd advise you to make sure that the lock-out is solid every rep.