When we were subdividing/redoing lots the requirements from our city involved road frontage (every lot had to have the required number of feet facing an official road (as I remember it was 90 feet at that time and in our zone). Lanes were not legal in the city anymore, so you could not do a long big driveway back to access the other lots. If you had to make a road past the house to make frontage for the other lots it had to be something like 54 feet wide with curb and gutter on both sides, plus lighting. It was not cheap to utilize narrow, long pieces of land with limited frontage. You might only be able to reasonably split a lot in two with the frontage you had under conditions like that.