Directly from the ten ryaku no maki we begin with learning how to free our arms and bodies when they have been grabbed from our training partner. What is important to keep in mind is the escape vs. fighting back perspective.
In the ten ryaku no maki you just learned how to move your body correctly with budo taijutsu flavor, and now when grabbed you are not moving- your training partner has stopped you in place either by grabbing your arms or body.
Hajutsu is about freeing yourself so you can keep moving again.
On a goshinjutsu (self-defense) level being able to move is critical- even if you do nothing else, but just keep moving that increases your ability to say safe as it’s always harder to hit a moving target.
This is the secret behind one against many (ichi tai tatsu).