"Dog whistle editing" is attention to distinctions of usage that only other copy editors can hear.
Perhaps the most notorious of these wastes of time and attention is the over/more than distinction, observed only by American newspaper editors. Seriously. When I've mentioned this quibble to lexicographers, they've given me blank looks, over having been in use in the sense of more than since before the Normans corrupted Anglo-Saxon. And yet, when the Associated Press Stylebook, in a rare outburst of good sense, dropped this entry a couple of years ago, there was a great wailing and rending of garments, accompanied by vows to hold on to the distinction until it is pried from cold, dead hands.
But there are more.
aggravate, irritate Supposedly one is irritated first, aggravation setting in when the irritation grows more intense. But Merriam-Webster's Dictionary of English Usage points out that the initial "makes worse" sense was expanded into the "annoy" sense back in 1611.
careen, career Theodore Bernstein's Careful Writer is one of the traditional usage manuals insisting that careen means "to tilt over to one side," as sailing ships were once careened on beaches for repairs when no dry dock was available, and career means "to move recklessly, at high velocity." But if you go to the Corpus of Contemporary American English and begin sifting through the hundreds of entries for career, you are going to find nouns. If you check out careen at COCA, you'll find ample citations of the verb in both the "tilt" and "hurtle" senses. The American Heritage Dictionary lists both senses for careen, without a usage note.
compared to, compared with The distinction is that compared to indicates only similarities, compared with can indicate both similarities and differences. Merriam-Webster's Dictionary of English Usage examined the evidence and found that compare to usually indicates similarities, according to the rule, but that compared to and compared with have become functionally interchangeable.
convince, persuade They will tell you that one is convinced of but persuaded to, but common usage so widely allows convincing someone to do something that the objection is idle. I used to make an effort to draw a distinction that convince is a stronger word than persuade, because you can be persuaded to do something that you are not convinced is right. But that distinction never got any traction with the readers of this blog, so to hell with it.
diagnose Diseases are diagnosed, not patients, you may have been told, but usage ignores the distinction, and has done so for some time.
gantlet, gauntlet It galls me to have to give up on this one, especially since Garner's Modern American Usage holds that it is still a meaningful distinction to maintain. But Garner concedes that the trend is for gauntlet to mean both the challenge and the ordeal, and Merriam-Webster's Dictionary now merely lists gantlet as "variant of GAUNTLET." Increasingly, this is a whistle you can only hear if you are of a certain age.
like, such as As with over/more than, you can talk to lexicographers who will think you slightly addled to maintain that like cannot mean such as, because they have paid attention to centuries of usage while you have been upholding a hoary quibble that not even the AP Stylebook insists on.
nauseous, nauseated The struggle to establish nauseous as meaning "to induce nausea" rather than "to experience nausea" rose in mid-twentieth-century American usage manuals, and it has never gained much ground anywhere but in American usage manuals. When Woody Allen says in Sleeper, "Sex and death. Two things that come but once in my lifetime, but at least after death you're not nauseous," there is no misunderstanding what he means.
since, because There is really no warrant, historically or in contemporary common usage, to limit since to temporal rather than causal senses. The two words are interchangeable. The common phrase "since you asked me" is not misunderstood in context to mean "from the time you asked" instead of "because you asked."
titled, entitled The supposed difference is that entitled, being related to entitlement, cannot be used to mean "bearing a title." And I vaguely recall coming across the idiosyncratic opposite warning that books are entitled because titled means "holding a title of nobility." Here's a trick: When you come across "Umberto Eco's novel, entitled The Name of the Rose," change it to "Umberto Eco's novel, The Name of the Rose," and spare yourself the aggravation.
If any of these dog whistles sound odd or unfamiliar to you, you are to be congratulated for not having developed bad habits that you need to break.
If you know any of them, and they seem important and meaningful to you, go ahead and maintain them; this is America. But you might want to consider whether you should be focusing your attention on sounds that readers can actually hear.