Re: Customize and autoloaded libraries

[Richard Stallman]

    The downside is that simply putting an add-hook in your ".emacs" may
    cause a package to become loaded (but using customize to add the hook
    won't make the package loaded at start).

That is true.

    A variant would be to change add-hook so it added the hook to some
    symbol property, and the actual value of the hook wasn't affected
    under the hook was declared with defcustom, or ran with run-hooks (for
    hooks ).

This is a good idea.  In fact, I had the same idea just after
reading the previous paragraph.  But with a twist:

    It would break code that use hooks but neither defcustom or run-hooks.

The twist was twist to prevent this problem.  add-hook could do the
job right away, unless the variable has a custom definition.