Daniel Klein, Professor of Economics at George Mason University and Editor of Econ Journal Watch, asks:
What probably would you put on the truth of a broad hypothesis of deliberate centrality?
Here's more background on the question:
In a Word or Two, Placed in the Middle: The Invisible Hand in Smith’s Tomes, by Daniel B. Klein and Brandon Lucas: Abstract: The meaning and significance of Smith’s expression “led by an invisible hand” has been long debated, and especially lately. We speak to the large debate only in fine, by focusing on the conjecture, first hinted at by Peter Minowitz, that Smith deliberately placed his central idea, as represented by the phrase “led by an invisible hand,” at the physical center of his masterworks. We bring supportive evidence and argumentation to the conjecture. The four most significant points developed are as follows: (1) The expression “led by an invisible hand” occurs pretty much dead center of the 1st and 2nd editions of Wealth of Nations, and of the final edition of the volumes containing Theory of Moral Sentiments. (2) The expression in WN drifted only a bit from the center, only about 5 percent from the center in the final edition (and even less if the index is excluded). (3) The rhetoric lectures show that Smith not only was conscious of deliberate placement of potent words at the center, but thought it significant enough to remark on to his pupils, noting that Thucydides “often expresses all that he labours so much in a word or two, sometimes placed in the middle of the narration.” (4) There numerous and rich ways in which centrality and middle-ness hold special and positive significance in Smith’s thought. In conjunction with larger considerations, these points may be helpful in assessing the significance of Smith’s famous phrase.
Here's a figure showing centrality through the 7 editions of each work.
This is an attempt to rescue the invisible hand from critics who argue that the invisible hand idea that is attributed to Smith was not a central part of his writing (e.g. see Gavin Kennedy).
In answer to the question, it doesn't seem very likely to me that this was intentional.
Note: If you are unfamiliar with the debate over the invisible hand, here is Gavin Kennedy:
...Lost Legacy has never been slow in criticizing the ‘Chicago Adam Smith’, a person with ideas that are far from the ideas of the Adam Smith born in Kirkcaldy in 1723.
George Stigler’s boast that “Adam Smith is alive and well and lives in Chicago” (1976) reflects to invention of the Adam Smith of the “invisible hand” (a mere metaphor for Adam Smith whose single use of it in Wealth Of Nations referred to the unintended consequences of the risk-avoidance of some, but not all merchants ... who preferred the home trade), and had nothing to do, at least in Adam Smith’s mind, with how markets worked, ... or how the price system worked.
The belief that the “invisible hand” was a significant ‘idea’, ‘concept’, ‘theory’, or ‘paradigm’ was wholly invented in the 1950s by neo-classical economists on the back of general equilibrium mathematics ... and in support of a worthy criticism of Cold War, Soviet central planning. It is now taught in every economics 101 class as if it had historical validity, mainly by people who have never bothered to read Wealth Of Nations. ...
Update: See " Yet Another Note on Adam Smith's "Invisible Hand": What It Is and What It Is Not" by Brad Delong.