Also boundary cases aren’t necessarily extreme, e.g., if you have some kind of optimizing buffer that kicks in when there are at least 10 players, 9 player and 10 players (and going from 9 to 10 and conversely) are boundary cases but not extreme cases.
Also boundary cases aren’t necessarily extreme, e.g., if you have some kind of optimizing buffer that kicks in when there are at least 10 players, 9 player and 10 players (and going from 9 to 10 and conversely) are boundary cases but not extreme cases.