When I talk about "timing" in the Snatch, Clean, or Jerk, I am referring to receiving or "catching" the bar in a quick and stable position. This smooth timing of the bar is essential to controlling heavy load. In order to make my athletes faster and more functionally stable, I promote the concept of elbows & feet reacting together.
I often cue the athlete to "lock and land together." If the athlete can consciously do so, simultaneously, it will not matter how heavy the bar is. The athlete can receive the barbell in a strong, functionally stable position. Note: I like the loud sound of the feet when catching the bar, but I do not necessarily want a dramatic stomp. The sound of the feet can be made without excessive airtime. What I am looking for is a swift shift of the feet, which must be learned. This timing of the bar can be made proficiently by ensuring the elbows and feet work together.