Thanks for everyones help here. I finally put two and two
together... here is the resolution for the archives.

        "Consider the following" (I have always wanted to say that):


        BEDROCK:(ZXKENB):
        BEDROCK:(ZXKENB):
        BEDROCK:(ZXKENB):LISTF @;temp
        BEDROCK:(ZXKENB):
        BEDROCK:(ZXKENB):LISTF @;temp
        DUPLICATE TEMPORARY FILE NAME  (FSERR 101)
                                 ^
        File system error 101 encountered on list file. (CIERR 425)
        BEDROCK:(ZXKENB):
        BEDROCK:(ZXKENB):
        BEDROCK:(ZXKENB): LISTFILE @;TEMP

        TEMPORARY FILES FOR MGR.SGAIIDV1,ZXKENB

        TEMP.ZXKENB.SGAIIDV1
        BEDROCK:(ZXKENB):
        BEDROCK:(ZXKENB):

(Do not confuse ";temp" with the option ";TEMP".   That option is only valid
for the LISTFILE command, not the LISTF command. Using it with LISTF you are
specifying/creating the name of an output file - a temporary file called
"temp".     LISTF [fileset] [.listlevel] [;listfile]   )


The behaviour in the example above is clear that temporary files can only be
used once. Rather than warning the user that a file already exists and
providing the user with the option of deleting the file, an error is
generated instead. This is the normal expected DEFAULT behaviour of MPE when
accessing/creating temporary files..

This has implications to PowerHouse QUIZ subfiles however.  You cannot use
file equates to create TEMPorary subfiles  (aka, FILE MYSUB =
MYSUB.PUB;TEMP). PowerHouse allows you to RE-use subfiles. But this
behaviour conflicts with MPE's temporary file types - which do NOT allow you
to re-use temporary files (at least not by default). Rather than prompting
you to clear a previously existing subfile, MPE gets involved and generates
an error on the "re-use" of a temporary file... your QUIZ job will crash.
This is the reason we have the following (from my original post):


: file mysub = mysub;temp

    : quiz
     access myfile
     report summary mydata
     set subfile mysub
     go
     exit
   :
   : reset mysub
   : file mysub = mysub;temp
   :
   :quiz
    access myfile
    report summary mydata
    set subfile mysub
    go
 *W* The temporary subfile MYSUB has been deleted.
 *E* File error on dictionary portion of subfile.
 *E* DUPLICATE TEMPORARY FILE NAME  (FSERR 101)