>I'm not sure, but at a guess, K&R wrote curses and vi to avoid having to
>edit using ed.  They wrote C because the didn't like pdp11 assembler :-)

I'm reasonably sure that Bill Joy wrote vi, and I got the distinct
impression that people at Bell Labs regarded it with a bit of disdain
(I met people at Bell Labs in the mid-90's that were still die-hard ed
users, believe it or not).  I was once at a talk by Peter Salus, who
said that a quote that he always remembered from folks at Bell Labs
(I don't recall who) was along the lines of, "I've never felt the need
to look at more than one line of source code at the same time".

--Ken