I think we're at a place where using the phrases "Art of ...", "Science of...", and "Art and Science of ..." are not interpreted with the literal definitions of art or science in mind. Typically, in colloquial (as opposed to formal) writing, "art" comes with an understanding of "all the steps haven't been quantified and some intuition is involved" and "science" tends to be "here are the steps to take and the items to observe and the things to change in response."
So I disagree: there is Art and Science to, well, most things; including leading projects.
with pg's onlisp, you don't need any other source.
Relevant excerpt from the introduction
There are very few good references or tutorials on macro
construction. Paul Graham's On Lisp[ON-LISP] is one of the
exceptions. Every word of On Lisp is required reading for anyone
interested in macros. On Lisp and Graham's other writings were the
most important inspirations for the creation of the book you are
reading now. Thanks to Paul Graham and other lisp writers, the power
that macros provide programmers is widely discussed, yet is
unfortunately still widely misunderstood. Despite the wisdom regarding
macro programming that can be gleaned from a simple perusal of On
Lisp, few programmers make the connection between the macro and their
real-life programming problems. While On Lisp will show you the
different types of macros, this book will show you how to use them.
Having read about half of On Lisp, I think that's a fair claim. I am
very glad to be reading it, it is a wonderful book, and thanks to it I
know what a macro is and what it can do, but haven't really come away
with a good feel for when to use them myself in my own code. (It may be
that the logic of my code is too simple to require them.) Whether
Lambda Over Let lives up to its claim of showing how to use them, I
don't know. Definitely going to take a look.