In the police academy they teach the retreat and move to the side as the "tactical J". Usually it is practised as moving to the strong side and turning your body so your pistol is away from the attacker. The theory is that an attacker (particulatly a drunk one) will have more difficultly tracking you than if you went staight back. (basic stuff to an aikidoka) However, I would submit to you that this type of technique is best suited to someone who is armed/and or willing to counterattack. The movement lets you take control of the timeing and distance of the engagement, but is not an "escape."
Turning and running is basicly a two step process, and the attacker only has one step (i.e. pounce on the good guy etc.). A workable Aiki answer is to enter DEEPLY with irimi as you are attacked. If you find yourself in a position where atemi or a technique is possible, then have at it, if not run like hell passed the attacker. The he has to turn and chase, so the slower responce is forced on him.