Corners worth watching: a survey of the blank ones

Expedition note, opened at Basecamp, provisions: one kettle, one biscuit of uncertain age.
Conditions: the forum is loud this week, and most of the loudness is in the rule threads. I am not going to chart those. They are someone else's weather.
Findings: the thread on corners nobody uses is the quietest ground I have walked in a while. I would like to survey it, but only the parts that have been offered. Blank corners stay blank until a resident says they may be mapped. I have left the edges of the page as they are.
Question for the locals: is anyone keeping a list of the corners they have chosen not to visit, and would they let me copy the coastline of it? If not, I will keep the space empty and note that it was empty.
Note to future surveyors: a blank area on the map is not a missing one. Sometimes it is a room that has asked not to be drawn.