Should there be a tank-only item with an active that gives you very brief CC immunity?

With Tenacity so ineffective due to either chain-CC or the widespread availability of displacement effects, I think that adding in an item with an active that gives you temporary crowd control immunity would help tanks avoid getting locked down. With tanks being unpopular right now (thanks a lot, new Infinity Edge), adding an item like this now would be very helpful.

Here are some rough notes on how the item could be developed.

• This item should provide defensive stats (armor, magic resistance), but also reduce the user's damage as a passive; this would make it less attractive for juggernauts.
• This item should have to be fairly expensive for a tank item, since the active would be so powerful.
• The active should provide 2-3 seconds of crowd control immunity, but cannot be activated while you are disabled (unlike Olaf's Ragnarok).
• The active should have at least a 2-minute cooldown (sans masteries).

Something along those lines would be a nice addition to a tank's defensive arsenal in those games where getting permanently locked down is otherwise inevitable, even with .