The Case for Durative Actions: A Commentary on PDDL2.1
  The addition of durative actions to PDDL2.1 sparked some controversy. Fox and
Long argued that actions should be considered as instantaneous, but can start
and stop processes. Ultimately, a limited notion of durative actions was
incorporated into the language. I argue that this notion is still impoverished,
and that the underlying philosophical position of regarding durative actions as
being a shorthand for a start action, process, and stop action ignores the
realities of modelling and execution for complex systems.
