Haha of course there's a goat token! ty =P

@JStrodt_WMDE So I take back what I said via email... while this wouldn't be terribly difficult to implement, it will be very expensive. The gadget runs queries on every page. The ArticleInfo gadget gives you quick statistics that we can fetch in real time, in under a second. But for textshares, we have to go through every revision in the article. This will be too slow for an API.

I was wondering how WikiHistory did this, and now I recall -- it computes the textshare information ahead of time with a bot, and stores it in a database. This allows you to quickly get the textshares for a given article, provided the bot isn't broken. XTools does not feature such a bot, and it's highly unlikely we would implement something like this :/ A bot seems fragile, and also XTools is meant to work on all wikis (even non-WMF wikis), not just the few wikis we have the bot running on.

So I'm sorry to say the gadget idea probably won't happen from us :( But I can still make the actual ArticleInfo tool (not the gadget) show the textshare percentages just like WikiHistory did. Even as it is now, you can still see the "Top editors" of an article using XTools (example). You'll just have to ask for the data on-demand using a link, rather than have it show up directly on the wiki page. I see you're already linking to ArticleInfo in MediaWiki:Pageinfo-footer (shown on the action=info page). For further convenience, you might add the link to MediaWiki:Wikimedia-copyright just like you are doing with the Pageviews link.