He's talking about the guy who did Viaweb, which became Yahoo Store. First server side application which allowed designing a web site via a browser, written in LISP.
The way to deal with overoptimistic programmers is to put them on maintenance programming, fixing bugs in the code of others, for a few months or years.
Um, I'm assuming that you are purposefully avoiding mentioning Paul Graham's name. You know, they guy who wrote the software that runs the site on which you are posting your comment. :-D
(wasn't sure if you were trying to be funny by doing so, or if there is something else relevant I've missed in the many posts above and below this that I haven't read)
The way to deal with overoptimistic programmers is to put them on maintenance programming, fixing bugs in the code of others, for a few months or years.