@kentpitman @screwtape Here is one version of the story that leans heavily on recollections from Stallman and Steele: https://www.codeartnow.com/hacker-art/macsimizing-teco
Dan Weinreb wanted to set the record straight: https://web.archive.org/web/20121107150708/http://danweinreb.org/blog/rebuttal-to-stallmans-story-about-the-formation-of-symbolics-and-lmi
Subsequently some email conversations appeared and Steele revised his story. https://onlisp.co.uk/On-the-Origin-of-Emacs-in-1976.html
MACSimizing TECO: A Note on the Invention of EMACS Adrienne…
www.codeartnow.com