Re: doc elisp intro cross reference fixes

[Richard Stallman]

    Maybe one needs to think more radical thoughts: Where is the sense in
    allowing me to do (setq global-font-lock-mode t) even though it has no
    effect?

    Now, maybe changing setq to invoke the Custom setter would be too
    weird.

    But maybe it is possible to change Custom such that it doesn't need
    those variables?

Setting the variable with setq may not be useful, but looking at its
value is useful.  It makes no sense to eliminate the variable.