Only

 "And," she added, "they only have one Harrington, thank God! The longer they leave her at Sidemore, the better I'll like it." -- War of Honor by David Weber, pg. 478

"... But of course, she's only doing it because of the absolute sanctity of her holier-than-thou, save-the-universe, rescue-mankind-from-original-sin ideology." -- Honor of War, pg. 376

These people were clearly maintaining operational security, and like everyone else in the briefing room, McKeon could think of only one star nation against which any Havenite operation in Silesia could possibly be directed. -- War of Honor, pg. 667

There may not be a single aspect of grammar that is currently so ignored and abused than the placement of the modifier "only" (and "just" when used in the vein of "only"). Because "only" acts as both adverb and adjective, it might modify nearly any word in a phrase, clause, or sentence. What causes such problems, I do not know, because it takes only a modicum of thought to place it correctly. (Of course, most people do not really think about much at all, forget about grammar!) Apologists excuse such incorrect usage with a variety of arguments, but the most cogent and reasonable of these is that in most such cases, the true meaning cannot readily be misconstrued.

However, those apologists miss the main point. The onus of information transfer is on the speaker/writer. That is, the person transferring information needs to make it clear to the receiver what s/he intends, to not allow for any possibility of misunderstanding. That is the sole reason that there are rules in grammar, so that all know what to expect and where to expect it. Yes, in most such cases of misplacement of "only," one would have to stretch to misunderstand the intent. However, my experience suggests that people get lazy when not following the rules and when the situation is important to get usage right, they strike out, as they've become accustomed to being lazy. For the same reason, it is important at all times to use one's turn signal appropriately when driving a car, else when you really need the driver of the car behind you to understand your intent, that person may be completely unaware that you plan to turn because you haven't used your turn signal; you have fallen out of the habit of doing things correctly!

In the first quote, above, the speaker is intending to indicate that she is glad that only one Honor Harrington exists.  The placement of "only," however, implies something else, nebulous I grant you, but something else. That is because it is placed immediately before "have," a word that, as a verb, could certainly be expected to be modified by "only." The second quote is marginally more obvious as being incorrect. These might be just minor lapsus in copy editing (but which really ought to be caught), if it were not for the fact that the book and series are riddled with examples of incorrect placement of "only." Even that might have been a conscious style decision by author or editor, except for the fact that there are numerous examples in the same book, as in quote #3 above, in which the use of "only" is correct. These three examples do not differ in any material way. I infer, then, that author and editor(s) did not care or, worse, did not notice, that usage differed.

If we follow the apologists, should we, then, cease to find it important where other modifiers are placed? Shall we just willy-nilly string a bunch of words together and expect the hearer/reader to understand our intent?  That is, shall we appropriate put the modifiers different in places turning lucid our thoughts into mush so much?