I know that I speak for many journalists—and many others—when I say that it is perfectly possible to write after lunch, even if, or particularly if, you have had a bottle of wine. It is simply not possible to do this after dinner; not after booze. I don’t know anybody else who is capable of knocking out first-class copy after a long day and a drunken dinner. There must have been something unique in his metabolic pathways; and what makes it even more astonishing is that most of the time he didn’t even write. He dictated. He would gather his thoughts and then, wreathed in tobacco and alcohol—and perhaps wearing his monogrammed slippers and the peculiar mauve velvet siren suit made for him by Turnbull and Asser—he would walk the wooden floorboards and growl out his massively excogitated sentences. And that was barely the beginning of the word-processing system. Typists would struggle to keep up, but on he jawed, even into the small hours of the night, licking and champing his unlit cigar. Sometimes he would take them with him into his tiny and austere bedroom, and then while they blushed and squeaked he would disrobe and submerge himself in his sunken Shanks bath and continue to prose on, while they sat on the floor and pitter-pattered away on the specially muffled keyboards that he preferred. The sheaves of typewritten paper he would then correct and amend by hand—and we have innumerable examples of his cursive blue-inked marginalia—and then the results would be typeset as they would appear on the page; and even that was not the end. Now I pace across the room to an upright sloping bureau that is set against the wall, like a newspaper-reading slab in a club. It was here that he engaged in the final exercise of word-processing, a ritual that we would now perform effortlessly with our Microsoft programmes. He would fiddle with the text. He would switch clauses around for emphasis, he would swap one epithet for another and in general he would take the utmost delight in the process of polishing his efforts; and then he would send the whole lot off to be typeset again. It was a fantastically expensive method of working, and yet it enabled Churchill to produce not just more words than Dickens, or more words than Shakespeare—but more words than Dickens and Shakespeare combined.
Dictating work seems absurdly impractical and "expensive." But, perhaps that’s how you scale up. As with most improvements and transformations, there’s no magic, there’s just doing new, often weird, uncomfortable, and costly things.
From The Churchill Factor.