Re: reducing defface redundancy

[Richard Stallman]

    Well, there are two interfaces used by the (current) custom face UI:

      * The current-display-type-only interface, which is the default.

This is the hard case.  Yes you can flatten the nested spec and have custom
operate on that, but the hard part is how to alter the nested spec
based on the user's customizations.

    However, for the 1st UI (current-display-type-only), it might be a
    useful try and detect changes to `common' attributes and preserve a
    modified version of the original defface spec, instead of just trashing
    it as the UI does now.

Getting this right is the hard part.

    Anyway, my point is that the new grammar won't make anything worse, and
    may provide some additional leeway for improvement.

Yes it makes something worse.  It makes the effect of cutsomizing
the face problematical.  At present that is not so.