Note: this post is written more for the benefit of visitors and will be used as a reference. Regular LL contributors do a fantastic job complying with the rule.
Back on January 1, I wrote a post cajoling the community to help us when it comes to moderating the site by making an increased use of the flag link when appropriate. Traffic on this site has grown tremendously and continues to grow and I'm sure many of us tremble with anxiety about what the new season of game threads will entail. Even beyond those threads, there are roughly four front page posts per day on average plus a whole host of diaries and the 1,000 or so comments that go into the OTs. It's a lot of ground for us as moderators to cover and we need the community's assistance. Which is where flagging comes in and I refer you all back to the linked article above for more on the subject.
What does flagging have to do with subject lines? Why do we require them in the first place? It's been asked many times before, and we give the same general answer each time; that it allows people to collapse comments (very useful when comments are images, GIFs or walls of text) and that it helps with moderation by giving us direct links to flagged comments. I've seen some people, even other moderators, express surprise at the second part so I decided to provide a direct illustration.
To do so, I flagged two comments by user westbrook; hopefully he doesn't mind*. When I, as a moderator, view our moderation dashboard, there is a section where all recent flags are displayed. If flags are appropriately used, that dashboard is by far the single easiest way for us to keep tabs on the comments. Here is what it looks like:

With the subject line present, I can monitor the dashboard and quickly jump to flagged comments to investigate if any action needs to be taken. Without a subject line, I get nothing and have to manually hunt for the flagged comment.

*Note that comments without a subject line are prohibited at LL and warrant being flagged.
3 recs | 18 comments
So tempting
To make a comment without a subject heading in this post.
zeeehjee - April 3, 2010
Way to nip that in the bud.
DrunkAmerican - April 3, 2010
I approve this message
If I i were running for office, anyway :)
New England Fan - April 3, 2010
I actually hope the spammers in China
don’t find out about this
Freneau - April 3, 2010
They sure have been stubbornly persistent.
abender20 - April 3, 2010
Seems like theres two new accounts showing up every day.
BrianL - April 3, 2010
Will SBN be addressing this in their next revision?
Janic - April 3, 2010
Is it possible at all to link a comment w/o a subject line?
Bearskin Rugburn - April 3, 2010
You mean like
this?
Wilder. - April 3, 2010
You click the date/time.
JonBBT - April 3, 2010
LL 1.0 was a million times better
Poochie - April 3, 2010 via mobile
Not with that chode JI around.
Eyebrows - April 3, 2010
My ears are burning!
JI - April 3, 2010
That, and bold text is obscenely easier to read and follow.
People that don’t prefer bold text to follow comments weird me out.
vr, Cap
CapSea - April 3, 2010
On the Phillies blog, The Good Phight
they never use the subject line to comment, it’s really weird. I was always criticized by the other blog members for using the subject line when I commented over there during the World Series last year.
44FAN - April 4, 2010
This is visually distracting
We don’t use subject lines at Let’s Go Tribe. I understand your logic, I just find the appeal of not using the subject line outweighs the benefits of using one (and I am one of the co-moderators). We find the bold text of the subject line visually distracting, particularly when it represents a clause of partial sentence carried through into the comment itself. The bold text naturally draws your eyes, and by doing so draws your eyes away from the comment. It is harder to follow both the subject line and comment as a part of a continuous thread going from bold, to plain, to bold, to plain…
Just a little internet cultural variation I suppose.
APV - April 4, 2010
I respect your opinion, but...
I find the bold text makes it easier to distinguish one comment from the next. Without the boldness of the subject line, a thread just looks like on big ocean of text. Personal preference, really.
JLProck - April 4, 2010
I'm so used to how it's done here that I find it distracting
when the subject line is missing. I spend a fair amount of time over at Bloody Elbow, and no one uses them there.
Llewdor - April 4, 2010
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