From the hair pulling catfight I saw between Fran and Lois, I'd agree that a woman astride her opponent's stomach has an advantage in maintaining a double-fisted hairpull.
This series of clips strikes me as the way two older women might begin a hair pulling catfight. I can see them with their long hair up in elegant French Twists, using their hands to probe their rival's updo. Soon, they sink their fingers in the thick twists at the back of their heads and pull their opponent's hair down. Once loose, they begin ruffling it. After several minutes and dissatisfied with merely mussing up each other's hair, they get down to business and begin pulling, harder and harder. Eventually, the first handfuls of hair are ripped out by the roots as the two mature ladies commit themselves to a serious hair pulling match.