That's WAR in a nutshell.
The thing is, though, you won't be one-shotting any raid instance your first time in there. If you happen to get hit by something hard, you'll know what it is and when it's coming next time. That's the key to good IB usage - knowing when you'll need it and when you can freely use it before needing it again.
That said, you do have ogcd CDs you can use in panic situations. Vengeance and Thrill + Convalescence are made for them (though obviously better paired with IB).
