Nope, haima is a stacking shield mechanic which refreshes the shield only when the current shield breaks. It's used for weakening multiple successive hits /autos, not for tankbusters (unless said tankbuster hits multiple times in one instant). If the tankbuster is coming and you throw a haima on the tank at low hp, the tank's most likely goanna die before the rest of the stacks get consumed.
Sage's parallel to Excog is their 10% mitigation upfront 600 potency heal. - Same cooldown, just different usage.