That's a great article, thanks for sharing. I think this reinforces my thesis here. You can tell from the article that at the time, Lisp needed to prove itself

That's a great article, thanks for sharing. I think this reinforces my thesis here. You can tell from the article that at the time, Lisp needed to prove itself in the mind of people as "fast enough". That seems to be the intent of the article. Given a good compiler, it may be just as fast. I'm not trying to bash Lisp, I love lisp, I use it all the time. And when I say "fast enough", I know lisp is manageably fast, maybe custom hardware could have made it equally viable, maybe it only needed a more sophisticated compiler more widely available at an affordable price, but in practicality, it had more hurdle to overcome than other languages to meet the bar of the time. Imagine an alternate reality where Lisp was clearly fastest. Where its semantics mapped very closely to commodity hardware of the time, and where Fortran, Algol, C, etc. semantics are all further removed from those hardware instructions, making them require more sophisticated compilers or very expensive specialty hardware to have them perform as well as Lisp. I feel it in such a reality, I can't see why C would have become the language of choice and not Lisp.