Alan Orr Wing Chun Questions 6 -Turning in Chi Sao

[guy b.]

That's cool.
Then what is it?

Here is what I already said:

I think it is a drill to develop, reinforce and correct errors in lines of attack

[YouKnowWho]

I believe WC Chi Shou should also include, I try to touch your arm, you won't let me. You try to touch my arm, I won't let you. It will be a nice "intermediate step" before moving into free sparring.