Re: compare-windows - synchronize points

[Richard Stallman]

    I forgot to mention that with small number it fails when an insertion
    contains the same substring which follows after an insertion.  In this
    case it finds the closest substring (in inserted text) instead of
    original text unchanged in both files.

I can see how that would happen.  It suggests an idea to me.  The idea
is to search for a larger matching substring first, and then try
smaller matching substrings.  It's the same kind of idea as first
trying smaller search ranges and then larger ones.

Anoter idea: it could search first for an entire line (with a certain
minimum length) of match between the two windows.  After finding that,
it could look within the mismatched areas for smaller partial matches.

Want to try those approaches?