I would not accept that every terrace house in the development is in the same position. When you exit the a terrace houses you can go left or right along the front of another terrace house to access an escape point further down the way.
You cant design a means of escape through an adjoining property. The adjoining property may have grass, or pebbles, or loose stone and a wheelchair cannot move through this, or a person using walking aids, that's the reason Part M calls for a 900mm hard standing path from the car to the entrance or from the site boundary to the entrance.
Furthermore, when you move in, the adjoining owner can legally without planning erect a fence, build a wall to the front, thus making your escape idea null and void.