You still needs comments that tell what the content of a code file is supposed to do, no matter how clear the code is.
(And in scripting languages which doesn't declare parameters, like Python and old style Perl, you need to document what the parameters are.)
Like some one mentioned in this thread, languages tend to be judged by the quality of code produced by their worst user.
For once you can write unreadable code in any language. Even in C and Lisp. In fact there you can create bigger problems and more unreadable code.