Re: command loop untouchable; ARGGHHH!

[Richard Stallman]

    My first attempt was to make all history text have the read-only
    property.  This worked great for me, using GNU Emacs in X.  But everyone
    who used moo.el in console mode, or in XEmacs, reported that when they
    copy and pasted such read-only text, they could not edit the resulting
    copied text in it's new buffer, because the read-only property had
    travelled with the text.

Have you tried it in the latest development Emacs?
It should discard the read-only properties from the text when it is yanked.
This should be a workable solution.

Another solution is to make an overlay which covers that text, and
give it hook properties that detect attempts to edit the text and get
errors.