RE: doc of defining minor modes

[Drew Adams]

    >     > FWIW, I do not agree. It is sometimes useful to enable a
    >     > minor mode upon load, and there is nothing wrong with that
    >     > for normal (i.e. respectful) minor modes. If I'm missing
    >     > something here, let me know - what's the harm (vs "harmless")?
    >
    >     You don't want to enable the mode just by using customize
    >     (which can trigger loading of any lisp library).
    >
    > I don't? Why not? What example are you thinking about?
    > If a library is loaded by Customize, then it's loaded
    > - so what? And how common is that? If there is a specific
    > corner case here that causes a problem here, then let's
    > identify it.
    >
    > Presumably, any libraries loaded that way should not be allowed (by
    > their writers) to cause harm. If they would cause harm by turning on
    > a mode, then they should not do so upon loading. That's all.

    Unpredictability is harm enough.

What's unpredicable? Can someone please provide a concrete example of the
problem? I'm not getting it. The doc and comments made here so far
constitute only vague warnings - what is the problem?