Mike - I take it you are taking the mickie
So it appears that if one is looking for info which might affect the actual flight (and what on earth is the point is getting Notams for other places????) the Narrow Route Briefing is 100% sufficient in all case.
As to the original question, the effective shape of the area reported must be a "lozenge" because each object described in the Notam is defined by a circle whose radius is chosen to be slightly larger than the geographical area being covered. In many cases, ludicrously larger but that's another subject...