When the language develops useful distinctions of meaning, Henry Fowler thought, scrupulous writers strive to maintain those distinctions.
Thus it still makes sense to insist that imply and infer are not interchangeable and that cement and concrete are not quite the same thing.
But a good deal of advice about language attends to distinctions that are so minuscule as to be a waste of time to uphold (lawyer and attorney in all but the most technical legal contexts) or, worse, arbitrary and artificial (over and more than).
A reader recently commented on his difficulty in maintaining the distinction he had been told about — he’s not a native speaker of English — between like and such as.
He is joined in bemusement by the editors of Merriam-Webster’s Dictionary of English Usage, who say this about the supposed necessity of using like for resemblances and such as for examples*:
“[T]he issue of ambiguity, which evidently underlies the thinking of those who urge the distinction, is probably much overblown.”
The entry cites a number of examples, commenting about them that in some “you cannot be sure whether examples or resemblances are intended, but the meaning of the sentence works out to be the same under either interpretation. And in none of the examples that follow can you detect any ambiguity of meaning, either as they are written with like or as they would read if you substituted such as. …”
My advice: Don’t listen for whistles that only dogs can hear.
*You can, by this reasoning, look like McIntyre, but not be an editor like McIntyre. You could be, if fate were cruel, an editor such as McIntyre. Not even the Associated Press Stylebook goes for this one.