Perhaps that's why they find this book more useful and rewarding than many an amateur reader might? As another reviewer of the book (Mr Hanna, over on the Amazon UK webiste) points out 'International relations, rather than military developments, are the focus of the work'. I suspect this will therefore be more popular with historians than wargamers or military 'buffs'? There were definitely stretches when I read with avid interest, but there were also times when I found myself slogging doggedly on, in an 1812 frame of mind (1812 Russia, that is, not 1812 U.S.), so to speak.
In many respects this is undoubtedly a very good book, Esdaile compiling and synthesizing huge amounts of Napoleonic scholarship and, if we take him at his own word, resolutely following his own line (particularly in asking whether Napoleon's character was a primary cause and motivating force in relation to this age of conflict), nevertheless at times it's the very all-embracing thoroughness of the book that's the problem; casting his net as wide as possible, Esdaile's scale and scope are huge and wide.
Given his emphasis on diplomacy rather than campaigning this approach renders his account, relative to many others I've read, fragmented and rather dry. However, Esdaile certainly succeeds in compressing a lot of information on numerous more obscure theatres (e.g. the Balkans, the Near East and Ottoman Empire, and the Americas, including the oft-overlooked Caribbean and South America), as well as the more commonly covered Euro-centric stuff, into a single volume.
At times, busy discussing one thing, Esdaile darts off to cover something else, happening around the same time but in another theatre. Sometimes, but not always, the two are clearly related, with developments in one theatre affecting possibilities in another, and the way this bigger picture emerges is amongst the books definite strengths, but this jumping around does disrupt narrative flow.
I imagine many readers of Napoleonic history, whether scholarly or just generally interested, relish the details of the often epic campaigns and battles. As Esdaile points out, there's plenty of that kind of material out there already. In preferring to trace the broader arcs of grand politics, he sacrifices this Holy Cow, and I have to say that, for this reader, the book's poorer for it.
It's now standard practice for books like this to draw heavily on primary sources, and Esdaile is no slouch in this respect. But his protagonists are almost exclusively bigwigs from the upper echelons, with their eyes on posterity. Very little detail comes from the groundlings, or has the simple candour their accounts often have. This is in keeping with his grand overview approach, but it does make for a drier (and sometimes more pompous) reading experience.
Personally speaking, I think books like this benefit from broader social representation. A good example of a book that not only manages this, but adds the oft-overlooked voice of womankind is Amanda Foreman's excellent A World on Fire (on the ACW).
Certainly amongst most the people I know (even many French people) Napoleon's still seen primarily as a warmongering imperialist despot, and therefore not to be admired! But equally, one has to concede that advancement via merit through the ranks of Napoleon's army, and in the secular French society of his time, was a more common thing than it was in the ranks of Ancien Regime powers, such as England or Austria (read Jack Gill's excellent three volume Thunder On The Danube series to learn how hamstrung Austria was in the 1809 campaign, on account of the dynastic and gentrified modus operandi that hamstrung the command level), and clearly - to my mind at least  Napoleon's character cannot be simply written out as an interchangeable cog in the machine of the history of the world at this particular time.
The French introduced the levée en masse, to defend the revolution, and Napoleon introduced annual conscription, which ultimately become know as the blood tax. This area of evolving warfare is not simple: the term blood tax tell us how unpopular conscription would become, but one can argue that from the levée en masse onwards, in the parlance of modern Europe, French troops were 'stakeholders', in a potentially more liberal state.
In England we avoided overt conscription, but not from magnanimity, but rather because introducing it might perhaps have fomented the kind of rebellion and change in the social order that the nobs here dreaded, especially having seen what'd happened in France. Against all this Esdaile quite rightly points out that, ultimately, 'Boney was a warrior' (as the old song had it), and only by acting collectively did Europe eventually defeat him and end the bloodshed. From this viewpoint Napoleon ends up in the odious company of Hitler, as destroyer of the peace.
Rather like Napoleon himself, whose contradictions - 'I have always commanded' and 'I have never really been my own master; I have always been governed by circumstances' - and whose alleged 'ruinous quest for glory' dominate this book, Esdaile tries to have it both ways: Yes Napoleon was a singular man, whose almost primeval force of character shaped events: 'it was the emperor's determination to eschew compromise... that made them [the Napoleonic wars] what they were'. But no, 'the history of Naploeon did not constitute the history of the world, or indeed, even Europe'! Hmm?
I read military history (well, history generally, and Napoleonic history in particular) like some people read novels, and my favourites are the books most like a novel in their characterisations and 'plot' momentum, etc. Ideally, one hopes, a history book can have this level vivacity without sacrificing objectivity. Some good examples include Barbero's The Battle and Zamoyski's 1812, but these are admittedly focussed on particular campaigns and battles, whereas Esdaile seeks to tell us about the whole period.
 I originally read and reviewed this book some years ago. Since then Andrew Roberts' book Napoleon The Great has appeared. He shares my position in respect of this particular aspect of the argument: Napoleon was a great man!