Trying to understand the fence drill

I am trying to understand the second part of the fence drill in the short
video that is on the home page of pitching.com The first part is to get
the feel of leading with the hip but the video seems to jump into the
second drill where the players are striding away from the fence.

The coach is working with the players on the drag line of their pivot foot.
What are they attempting to accomplish? It appears as if he is trying to
get them to understand the relationship of this drag line to their stride and
plant but I am not sure.

Does anyone have input?

Welcome!

I looked on the front page of pitching.com but didn’t see any videos about a fence drill.

Sorry. Try this. stevenellis.com The actual name of the drill
is the Hershiser Drill. So, you might have to search for it. Again, I understand the basic premise of leading with the front hip, but then the coach (and I believe it is Tom House) jumps into having the players look
at the drag line of their pivot foot.

Ok, the Hersiser drill is a Tom House drill. The dragline concept is his as well. The idea of the dragline concept is as follows…

You can used the dragline to determine your starting position on the rubber. Move your starting position left or right to get your dragline to end on the imaginary line from the center of the rubber to the center of home plate. This helps reduce or eliminate posture changes during the delivery.

You can use the distance from the rubber to the end of the dragline as an indicator of momentum. A goal to shoot for is 2 shoe lengths in front of the rubber.

Note that shape and direction of the dragline is not a concern other than as mentioned above. Don’t try to change these. Also, note that not all pitchers have a dragline. That could be an indicator of some other deficiencies. Or not. Curt Schilling didn’t have a dragline yet was very good.

What deficiencies could be indicated with no drag line?
Might a pitcher be lunging at the target? if so this could potentially lead to inconsistent release points.

Posture issues and timing issues (ie. early shoulder rotation) can lead to a short or non-existant drag line.