Mitigation question

[winsock]

It depends on the context.

Healing isn't damage mitigation. It has no impact on the amount of damage you'll take. This is in contrast to a skill like rampart that reduces your incoming damage.

Healing can mitigate your risk of death, so it is mitigation in the broader context of tank survivability; however, it's worth noting that when people talk about mitigation, they're usually talking about damage mitigation.