Hi 400bhp. David from The Sufferfest here. Actually, it's not set on that power curve. It's four discreet metrics tested in one, one-hour session which is then applied to pre-programmed workouts where APEX Coaching has mapped each effort in every one of our workouts to the appropriate metric.
That means that the targets above FTP will vary based on the specific workout and the intention of that workout (or even portion of the workout) relative to your 5 minute, 1 minute, and 5 second Full Frontal 4DP test values. As an example in Violator (a sprint focused workout with three sets of sprints that have various durations and recoveries), not all of the targets are based on 5 second or even 1 minute value, because by the time you get to the 1:1 ratio of work/rest intervals in the third set, it’s effectively a pVO2 max set (power at VO2 max), and therefore the target is set relative to your 5 minute power. Each Sufferfest workout varies to some degree how much and which of the 4DP targets are being used – but the big picture goal of 4DP is to more optimally have the app give just the right intensity of effort throughout the workout relative to the individual’s specific strengths and weaknesses.