The other day, someone asked me about the origins of the phrase “off the cuff”. I’ve always assumed that it had something to do with the old practice of writing informal notes on men’s detachable (and disposable) cuffs. And the OED’s entry agrees, glossing it as

off the cuff (as if from notes made on the shirt-cuff) orig. U.S., extempore, on the spur of the moment, unrehearsed

But as far as I know, the practice of wearing detachable (and sometimes disposable) cuffs ended by the time of the first world war or even before, while the OED’s earliest citation for this idiom is from 1938:

1938 New York Panorama (Federal Writers’ Project, N.Y.) vi. 157   Double talk is created by mixing plausible-sounding gibberish into ordinary conversation, the speaker keeping a straight face or dead pan and enumerating casually or off the cuff.
1941 Time (Air Exp. Ed.) 4 Aug. 1/1   Talking off the cuff to a group of civilian-defense volunteers he made them a little homily.
1944 Penguin New Writing XX. 130   In that scene, shot off the cuff in a shockingly bad light, there leapt out of the screen..something of the real human guts and dignity.
1948 Economist 3 July 17/2   Mr. Truman’s off-the-cuff comment.

So I figured that the OED just hadn’t researched the idiom adequately. But a fairly extensive search through various online archives only antedated the OED’s citation by two years, to 1936:

The Google Ngrams plot shows origin in the 1930s, and adoption between 1945 and 1960:

My searches also informed me that the early uses of the phrase included not only that improvised-movie-making sense, but also the sense of alerting others to a random event, or perhaps enumerating a diverse list of events, presumably from notes jotting on one of those cuffs. Thus in November of 1942, Billboard began a regular column listing random events, under the heading “Off The Cuff”. Here are (what I think are) the first two:

Here’s some information about those disposable paper shirt cuffs, from Giles Slade, Made to Break: Technology and Obsolescence in America, 2007:

What has been called “disposable culture” or “the throwaway ethic” began in America around the middle of the nineteenth century when a variety of cheap materials became available to industry. Innovations in the machinery of paper production, for example, made paper a practical substitute for cloth. The millions of paper shirt fronts (bosoms, as they were called), as well as the collars and cuffs that adorned nineteenth-century American men, owed their commercial success to this technological advance.

The beauty of these disposable products, as far as paper manufacturers were concerned, was that demand for them seemed endless. In 1872 America produced 150 million disposable shirt collars and cuffs. Men found paper clothing parts convenient because laundry services in those days were unreliable, expensive, and available mainly in large urban centers. America was still predominantly a rural culture, and before the advent of modern washing machines in the twentieth centruy, laundry was an onerous, labor-intensive task undertaken by women once weekly on Blue Tuesday. Single men simpy lacked access to professional or spousal laundry services. They bought replaceable shirt parts in bulk and changed into them whenever the most visible parts of their attire became stained or discolored.

And all the evidence that I can find suggests that the fad for disposable paper cuffs ended well before 1900. Thus “History Lesson: Glen Paper Collar Co. owners were inventors first“, The Saratogian 8/24/2009:

During the 1870s, a peculiar clothing fad swept the country. Disposable cotton-based paper collars were introduced to the upper classes as a way of maintaining a fresh, white collar rather than attempting to clean soiled cloth collars.

Some of the first paper collars in the country were manufactured two miles north of Ballston by Lindley Murray Crane, a paper mill owner and holder of three patents. Henry Mann’s father also manufactured paper collar materials in nearby Factory Village for some years under the partnership of Mann & Laflin.

Medbery and Mann recognized the potential, and rented space at the Blue Mill to establish the Glen Paper Collar Co. In their first year, the partnership produced 9 million collars. Soon they occupied the entire building. In 1871, they built a five-story, 60-foot by 40-foot addition, reportedly constructed in 20 days. They rented the old Waverly Hall for use as a packing station and salesroom.

Shipments of collars increased. At its height in 1875, the factory was producing 21 million paper collars and 5 million paper cuffs annually employing 150 people, becoming one of the world’s biggest producers. […]

But the fad died out in the mid-1870s. In 1876 Medbery moved to Newburg,New York and became a member of the firm James A. Townsend & Co., manufacturers of writing papers.

This leaves us with four possibilities:

1. Disposable paper cuffs remained in use, at least in certain groups, right up through 1950 or so;
2. Movie directors, entertainment journalists, and politicians continued to write on their cuffs long after the cuffs ceased to be disposable;
3. The expression “off the cuff” originated at some point around 1875, but managed to avoid appearing in print until 1936, and did not become common until the late 1940s, when the physical basis of the metaphor was long dead;
4. The expression was born when the metaphor was already long dead.

My feeling is that (1) is implausible (2) is silly, (3) is unlikely, and (4) is weird.

So what happened?

Update — from W.W. Aulick, “The Theatre”,  The Gateway (“a magazine of the times”), May 1913:

“Pop” Flannery, of the City News, found fault with one of the stage reporters because he made a pencil note on his cuff. “Not a bit like it,” declared Mr. Flannery, “only a make-believe reporter makes notes on his cuff.”

Master James Murray, who looks after the Evening Journal at the Courts Building, hadn’t heard “Pop” Flannery’s remark. Mr. Murray told the manager of the Astor–just in a friendly sort of way y’understand–that it was too bad one of the stage reporters hadn’t been told to make a note or two on his cuff. “It would have been a realistic little touch, do you see?” pointed out Mr. Murray.

This suggests that in imagination or in reality, certain sorts of people continued to make notes on their cuffs long after the paper-cuffs fad had faded. Still, I rather doubt that this was a common real-world practice in the 1936-1950 period.

Update #2 — And, as Robert Coren points out in the comments, there’s this scene from Modern Times:

Given how popular Chaplin was, this might well explain why the concept and the associated idiom rose to prominence in the ten or fifteen years after the movie was released.

In conclusion, as I’ve learned from the comments, detachable cuffs were used as note pads even when they were not disposable; and the practice of starching the cuffs of (white) shirts apparently made them suitable for note-taking even when the cuffs were not detachable. This helps us to bridge the half-century gap between the end of the disposable-cuff fad and the rise of the “off-the-cuff” idiom. Still, the idiom grew in popularity at a time (the late 1940s) when the actual practice of writing notes on cuffs must have been nearly dead, at best a memory for older members of the American population — or, perhaps more likely, an image from that Charlie Chaplin movie.