Looking at the example success with a twist listed for the heroic fortitude check, it seems to me that this is actually an example of failure but the story progresses.
Although this is an awesome example of a way to handle the player missing the CR, I wouldn’t call it success with a twist. The following text is in the section on interpreting failure but the story progresses:
It seems to me that this is the same concept listed in the fortitude example. I propose something more along these lines for success with a twist: