Wiki plugin front end edits not showing immediately

OK So i've got my first Wiki page up and running. When I test the front-end anonymous entry, while you can make edits and click save, none of the edits show instantly. In fact it doesn't necessarily show after numerous page reloads, but then will appear.

funnily enough, I tried creating a new page as an anonymous front-end user and it showed up instantly, but when I tried to edit it, again the edits didn't show immediately.

I've selected in settings that "anyone" can edit from the front end.

Is this normal behaviour? I'd have thought edits should show instantly.

Wiki page is: http://timtopham.com/wiki/pop/ if you'd like to test it.

thanks for your help!