Souba

Souba (相場 Sōba) is a term used in game commentary by Japanese pros. If a player makes a mistake leading to a bad position the pro may correct the mistake and show a natural resulting position and call this souba. There is an implication that this is the best both players can do in the situation.

Example:

Souba  

From this Japanese go magazine site, the commentary says that and are souba.