>>14
Getting to work on a non-trivial LISP project means you need to learn a new language, and all the stuff you use may not work.
In practice, that doesn't happen. When you follow the widely-accepted
BEST PRACTICES OF COMMON LISP MACRO WRITING, you end up with a small set of useful macros that extend the language in non-surprising ways (as in, not fucking up things around them, not polluting the namespace with random crap).
Sure, it's possible to make strange magic happen in unexpected places, but why would you want that? It would be like one of those IOCCC entries that
#defines everything to mean something totally different.