If I am thinking of the right thing- they are different combinations used for sparring. They've never been really stressed all that much by my instructors, but I know that other schools teaching the same style (American Kenpo) do teach and stress them in the lower ranks especially. I remember seeing them on all my old belt list papers thru green.........not sure if they go into the brown or black levels as well. Hope that helps a bit.
Not only do I make my students use them, I plague them with them during sparring sessions. Even my upper brown belts are not immune from the dreaded B1a.
I have found little use for the freestyle techniques. Those same movements are found in the self-defense techniques, why should we teach them twice. I concentrate much more on tactics, timing, and method of delivery. You really only need one good hand technique and one good leg technique to be an effective freestyle fighter. Learn to deliver those techniques in a variety of different methods and you can dominate most opponents.