Oh yes, I forgot about
The JCL Reference Manual
mentions /*JOBPARM L, but it's not clear if that is a positive to reverse NOLOG, or just an alias for NOLOG.
The equivalent of NOLOG can also be specified in the JOB statement, but the JCL Reference manual just refers you to a JES2 manual for more information, and that manual isn't very helpful. 40+ years ago I had this stuff memorized, but my memory banks have lost this information. In any event, JES2 exits can negate the standard JES2 scan.
Just an update to the previous post. Only the JES2 account field scan exits can affect this parameter.