Enable/disable Switch for AJAX Tabs
Ability to disable the AJAX feature of the tabs completely
The AJAX tabs feature is one that I think you really need to have a certain personality for. Plus, using them all the time can distract from how your non-Javascript users will experience the wiki.
Even more so, every time a tab is loaded via AJAX, this information is not recorded in the address bar, and refreshing, hitting back, etc, becomes an annoying experience for an end user. While a cookie can be added to save the current tab, this would conflict with the tab selected by the URL if you in fact intend to select a specific tab.
As such, an off switch would probably satisfy admins who are fed up with the tabs.