WRKACTJOB still a resource pig?

In the early, EARLY days of my AS/400 experience, I seem to recall that
WRKACTJOB was a resource pig, and could adversely affect performance. In
fact, there were a few shops I worked in that restricted access to that
command but had *ALLOBJ authority for everything else by default. And, I
also seem to recall that, instead of using F3 or F12 to exit the command,
you were supposed to use the System Request key, then take option 2 to "End
previous request"; that way, WRKACTJOB supposedly ceased to run in the
background.

I also seem to recall that all of this changed somewhere along the way to
V5R3, so that it is no longer a resource pig, and system performance is not
adversely affected by someone having it up on their screen all day,
refreshing it every few minutes or so.

The reason for this post is because I'm getting hammered by an aggressive
system cop/idiot (how this guy ever got hired here is a complete mystery;
think Dilbert's Mordac, "Preventer of Information Technology") who thinks
that our system's performance is in the crapper because I have WRKACTJOB up
all day when I'm on call for a particular production application, and I
refresh at 5 minute intervals. This is on a model 550 with, I believe, 8 GB
of memory (based on the sum of all Pool Sizes as shown on DSPSYSSTS; I can't
remember if this is accurate, or whether there is a better source of
information for this).

Right now, after having a job running this for over two hours, WRKACTJOB
shows the system's CPU at 70.7% and my job using 0.1%.
The total processing unit time used by my job thus far is 10.3 seconds.
Are there any other metrics that would be useful.

Ammo, anyone?

TIA,
- Dan