No cross traffic is the thinking, so the most dangerous situation - someone blowing through the stop sign at full speed - is less likely to be an issue, because it can only happen in on the road that's the top of the T, and since bottom of the T traffic always needs to stop, they are more likely to notice traffic that may blow through the sign.

If you look at modern American suburban streets, you'll see this idea in action. Most intersections are 3-way vs the grid layout common in older areas.