I just read through the first bunch of pages of both this book and SICP. I'm familiar with Lisp and I've been a programmer for many years, but I've never really been comfortable with Lisp. I have to say that SICP's approach seems much easier to learn from than this book's approach. Just a few pages in, and I felt like I understood how Lisp programs are structured well enough to figure out how any Lisp program works. The diagrams and exercises in this book just seem distracting and too verbose for the concepts they're trying to convey.
I think you've found the Lisp found in SICP more easier simply because Scheme (the Lisp flavour used in SICP) is purposely more concise than Common Lisp (the language from the this book).
Some teachers claim they could teach you Scheme in about one hour (see the excellent course of Brian Harvey).
Yes, it is more verbose. I don't think that SICP is a good introductory book (for all the well known reasons), though obviously I didn't know this at the time.
While I'm busy kicking the kids off of my front lawn, let me pause to say that it fails in the same way that Emacs fails---first thing I want to see in a book on a process (language, editor, what-have-you) is how to get it started and how to get out. Makes me a curmudgeon, but hey I'm old and came by it honestly... OBTW, it is otherwise a great read and since it is generic to all Common Lisps, of course it doesn't have the necessary how to start and how to stop---(clisp [if installed] and an eventual (quit)), for those who were wondering :)
