VMS Help FORTRAN, Format Specifiers, Reversion  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  When the last closing parenthesis of the format specification is
  reached, format control determines whether more I/O list elements
  are to be processed.  If not, format control terminates.  However,
  if additional list elements remain, part or all of the format
  specification is reused in a process called format reversion.

  In format reversion, the current record is terminated, a new one is
  initiated, and format control reverts to the group repeat
  specification whose opening parenthesis matches the next-to-last
  closing parenthesis of the format specification.  If the format
  does not contain a group repeat specification, format control
  returns to the initial opening parenthesis of the format
  specification.  Format control continues from that point.