Re: Question about Scotch production (peat versus charcoal)
Coincidentally, I just happen to be researching the history and specific characteristics of peat as used in the making of whisky for a chapter in a sequel to my first book on single malt Scotch. It's a fascinating subject!
I'm not at all sure just where the reviewer garnered that particular piece of information cited. But on the surface, it represents a falsehood. If I'm not mistaken, the use of coke, both to fire pot stills and to peat-reek barley during the malting process, only came to prominence when expanded mining of that resource permitted wider (and less expensive) availability. Prior to that time, peat, being a plentiful and cheap (though admittedly labour-intensive in terms of harvesting) commodity, was the fuel of choice. Don't forget that the decimation of the old-growth forests of Scotland had already made wood (and wood-derived charcoal) something of a precious resource. It would have the advantage of burning faster and more intensely than peat (a definite plus for illicit distillers 'on the run'), but its use would have more than likely been limited.
The transition from peat to coke first took hold in the Lowlands and central Highlands, and was largely concurrent with the industrialization of the whisky industry then occurring in those regions. More remote areas, such as the far north, the islands and, in particular, Islay, tended to retain the primary utilization of peat.
Nowadays, the tables would appear to have turned. And peat has therefore become a more prized fuel (not to mention taking into account the ecological aspects of its harvesting). Thus, the idea of using peat to heat pot stills (never mind the inefficiency element) is no longer a viable one. However, peat reeking of barley in the malting process remains a cornerstone of many of those smoky whiskies we love.
As to the relative qualitative issue as it relates to the aroma and taste of the whisky produced, one fuel is not necessarily intrinsically 'superior' to the other. It's simply a matter of exactly what profile a distiller is striving to achieve in their product.
If I remember correctly, some distilleries (such as Balvenie) even combine the heated air from both fuels (coke and peat) in their malting processes in order to achieve a less smoke-laden balance in their grist.
A footnote: Some individuals assert to this day that the utilization of peat as a fuel for firing pot stills actually resulted in a better whisky (than would be the case with coke) owing to a slower, more gentle heating cycle. And, of course, there are many who continue to espouse the superiority of direct firing of pot stills over steam coil heating systems (despite the added labour and maintenance costs).