I think all good programming has fixed and flexible or autoregulated parts.
S&S step loading has fix load, fixed volume, autoregulated rest, and fixed step duration.
AXE step loading has fixed load, fixed volume, fixed rest, and autoregulated duration (RPE going from 8 to below 7) - and flexible deloads. Therefore I have called it autoregulated step loading, as the length is individual.
KBSF Swings & GU step loading is fixed all the way. However, block length and volume increase are autoregulated.
KBSF LCCJs are originally programmed with fixed load, autoregulated volume, fixed rest, and planned deloads. In the article version Pavel recommends short consolidation steps for the 30 minute sessions.
Geoff Neupert likes fixed duration, fixed rep scheme, fixed load, autoregulated rest, and autoregulated volume with fixed block durations.
Of the different versions I prefer AXE's programming, as it allows me to focus on quality and prevents me from pushing too often (and thus from chasing fatigue).