This sort of “autocomplete” is actually fundamental to how classical composers were trained.
For anyone interested, I’d highly recommend reading Robert Gjerdingen’s article Gebrauchs-Formulas. https://www.researchgate.net/publication/259731561_Gebrauchs...
You can also listen to the transcript of four Russian composers, including Rachmaninoff, playing this pattern recognition and generation game at a dinner party in the late 1800’s: https://youtu.be/PlFPOWuwBHI?is=EKBK7QQkJs4MsTCU
Composers at the time could do this just by looking at sheet music and audiating, without using a piano.
To add to this: classical extemporization, post-Romantic period, also sort of fell out of favor as the composer began to pre-empt the performer and the "written note is sacrosanct" effectively became the de jure standard.
There's a great story around how Beethoven, perhaps one of the strongest improvisers of his day, completely upstaged Steibelt, a contemporary musician and by all accounts a bit of a charlatan. I'll include the entire quote verbatim from "The Lives of the Great Pianists" by Harold Schonberg.
I'm a little lost. What am I listening for in that video?
Check the article for the full context. It’s basically a musical version of exquisite corpse. One composer wrote the start of a phrase (on sheet music, without using a piano), then passed it on to the next composer, who continued the phrase based only on reading the sheet music.
This illustrates the extraordinary degree of audiation, or the cognitive ability to imagine music in the mind in a symbol-linked, systematized way, that used to exist in classical music.
Each composer could read what was just written, audiate how it would sound, audiate a continuation of the phrase, and then transcribe that aural imagination back to sheet music.
Classical jamming.