Some of the things he misses have existed in some environments, but haven't become part of the standard toolset that most Lisps provide. For example, the Lisp Machine had a List Callers command that would show you, and then let you visit, every function that called a given function. I worked at a place where we reimplemented that functionality for ourselves, by poking around in the internals of Allegro, but AFAIK no Common Lisp comes with this feature. It's too bad, I think, though admittedly grepping the source tree is usually an acceptable substitute.