Re: Add hook to end of `custom-create-buffer-internal'

[Richard Stallman]

    Those kinds of changes typically have the negative side effect that the
    buffer-setup code (i.e. custom-buffer-create-internal in this case) can't
    know the width of the window any more, so it can't fill text properly.

Is this a real problem or only a theoretical one?  I don't see
anything in custom-buffer-create-internal, or in cus-edit.el as a
whole, that tries to fill anything.  Where and how does that happen?
I just tried customize-variable in a narrow window and it did not
fill anything.

pop-to-buffer-dry-run, or anything like it, would have trouble
handling the case where special display calls a function to make its
own arrangements.