RE: worst RPG ever seen?

A lot of this may make sense "in context".  "Seek first to understand" is 
a good habit to get into.  For example I may do some code that may have
qcmdexc(mycmd:cmdlen);
// check error from psds
select;
when ExceptionId=*blanks;
  // ok
when ExceptionId='CPF2103';
  // library list entry was already there, ignore
when ExceptionId='CPFxxxx';
  // this choice location for rent
  // translation:  I plan on putting further error trapping in here
other
  // generic error handler
EndSl;

So for your GOTO NEXTONE they may have intended to put some error trapping 
in between.

And (without the despicable indicator) this might make more sense
0309.00 C     XTCHKH        IFGE      LDRDTH 
0310.00 C     XTCHKH        ANDLE     LDTDTH 
          // Falls in range, 
          //   do not display error,
          //   do not skip further processing
0311.00 C                   ELSE 
          // Otherwise, display error and skip all processing after endif
0312.00 C                   GOTO      TAG2 
0313.00 C                   ENDIF 


Rob Berendt