> I just found out that the emacs-wiki and muse people have been
 > struggling with the same problem.  Their fix was to use
 > inhibit-point-motion-hooks.  This points into the direction that a
 > search function gets thrown off into a loop by the point-motion-hooks.

Indeed binding `inhibit-point-motion-hooks' is more decent than my
earlier proposal.  Try the attached patch.