I think the results are unacceptably bad in some cases, and we should not run the script before it is improved:frwiki: DRY RUN: would rename 1547147 (3,'195.175.037.8') to (3,'Broken/184.108.40.206')
Should rename to (0,'Broken/User:220.127.116.11') (or something), in main namespace, so that we can easily produce a list of affected pages (i.e. Special:PrefixIndex/Broken/).test2wiki: DRY RUN: would rename 2987 (447,'Columbia_University') to (0,'Columbia_University')
Should rename to (0,'Broken/NS447:Columbia_University') (or something), so that someone can find out the original namespace (in this case, EducationProgram).bnwikisource: DRY RUN: would rename 1251 (0,'WS:COPY') to (0,'Broken/COPY')
Where did the WS: prefix go?avwiki: DRY RUN: would rename 7541 (1,'Википедия:Requests_for_adminship') to (1,'Broken/\xd0\x92\xd0\xb8\xd0\xba\xd0\xb8\xd0\xbf\xd0\xb5\xd0\xb4\xd0\xb8\xd1\x8f\x3aRequests_for_adminship')
It's not acceptable to mangle perfectly normal characters (but not ASCII) like this.
Also, I think the prefix Broken/ is also unhelpful (and not translateable). The script should take an option to specify a prefix, so that we can e.g. set it to T195546/ or maybe 2018-06-29/ or some other vaguely useful thing that can be used to find out where that page suddenly appeared from.