thanks edcny and millercarbon for your answers. Yes, the mighty piano tells you all's good, or not, on a number of levels.
Millercarbon, I like the cut of your jib. Zero, is the answer, of course. And so it turns out for 50% of my quick sampling this evening. You proved your own point. Inspired by that, I'll begin to answer my own question. But I won't do this little research again.
Of the 19 quickly plucked favourites lying near my record player, listed below, ten have zero “swing”, 7 around 1mm, a couple around 1.5mm and one delivered just today, 2.5 - 3mm, an otherwise barely played first UK 1977 pressing of the Steely Dan’s, Aja. Max Townshend refers to these as swingers ! And so they are.
You’d hope an ECM Germany pressing from the mid seventies, and Bach on Telefunken from 1968 would be zero, and so mine seem to be, and a Japanese Stevie pressing from the early 80’s is zero too. Yet that rather wonderful Ellington 1950 record from AP / QRP is 1mm out. I returned to their Ohio office from London a pressing of “Something Else” at 45RPM when to my dismay I found it swung 2.5 - 3mm. I’ve lost count of how many records I’ve declined that swung more than 1mm.
So I confess I hadn’t noticed the 1mm swing on the Ellington - but there’s fantastic music making on that LP that may cover the effects of the 1mm swing. Solo piano would be another matter.
Masterpieces by Ellington, 1950, 2014 USA pressing for analog productions, QRP, 1 mm
Beethoven PC No. 5, George Szell, London Philharmonic Orchestra, Decca FFRR 1950s,1 mm
Beethoven Pf sonatas, Clara Haskill, Epic Stereorama, USA, 1962, zero
Bach Cantatas, Telefunken, 1968, zero
Sun Ra, Sound of Joy, 1957, UK pressing, 1968, 1.5 mm
The Beatles, White Album, early 80s UK pressing, zero.
Earth Wind and Fire, Head to the Sky, late 70s-80s US pressing, CBS, zero
Lou Reed, rock ‘n’ roll animal, late 70s-80s US pressing, RCA, zero
Keith Jarrett, Koln Concert, 1975, ECM, zero
Pat Metheny, Bright Size Life, 1975, ECM, zero
Emil Gilels, Live Prague Spring Music Festival, 1973, Supraphon, 1 mm
McCoy Tyner, Nights of Ballads and Blues, 1980s US pressing, 1 mm
Stevie Wonder, Songs in the Key of Life, Japanese pressing, early 80s, zero
Art Pepper, Friday Night at the Village Vanguard, Contemporary Records, LA, 1980, zero
Art Pepper live at Ronnie Scott’s; Blues for the Fisherman, 1980, Mole Jazz London, 1 mm
Steely Dan, Aja, UK pressing 1977 2 1/2 to 3 mm
Miles Davis, Kind of Blue, 2010 US CBS pressing, zero
Miles Davis, In a Silent Way, MoFi, 2010’s, USA, 1 mm
Mozart’s Last Three Symphonies, Harnoncourt, Sony Europe, 2016, 1 mm