The David gives a basis for the heresy because he occasionally talks
about the importance of THE next action.  But when he talks most
explicitly about the number of next actions for a project, he clearly
talks about the importance of having AT LEAST ONE action per project.

One advantage of having multiple next actions for a project is that you
don't need to have a project review after every action completion if
the project needs to move closer to completion before the next weekly
review.  The "Pigpog" method of putting a complete linear sequence of
actions into a single NA is another way of moving a project along
without necessarily requiring a project review to identify next
actions.

Of course some projects need a review before the regular weekly review.
 The more uncertainty and discovery in the steps and the faster the
project needs to be done, the more benefit from intraweekly poject
reviews.