Electrician must pull another 25 feet of a set 3phase 4wire 500kmcm, only the head where the rope in attached to the capstan leaves no more room to pull.
To solve this problem a smaller rope with a number of half hitches is used to pull the cable set and my question is thus, what is the best method to tie the hitches for quick release and quick repositioning on the cable set?

I am not certain that I understand your exact circumstances but in the Navy we used half hitches anchored (furthest from winch) with a clove hitch, for a similar task. The half hitches will slide fairly easily to the new pulling position as will the clove hitch. In our case, the free end behind the clove hitch had tension on it, to keep the knot from working its way free. You might have to secure that free end. Even better might be to use several clove hitches instead of half hitches. They will also move easily once the tension is relieved. The clove hitch is formed by making two half hitches and sliding them together.

Glad someone knew, unless an electrician has knot or marine experience, we make it up at the moment we need it. We have all done it, need to pull large wire harness in a small distance, or other pulling conditions, we make the rope do what we want, but can't explain how.

We are also good at braiding, but never tell our wives or significant others.