The use of Spiritwalker’s Grace

Ok this one goes for all shamans out there. Why is it that Spiritwalker’s Grace is not used as much as it should be? (Can cast spells while moving for 15 sec with a 2 min CD) Especially for Elemental and Resto specs, this is an ability that should be utilized a lot more often. With the avg DS boss fight lasting approx 6 min, this ability can be used at least 3-4 times per fight! (Madness fight usually goes for 10 min or more depending on the raid group, so 5-6 times here alone) This is a huge advantage and depending what spec you are, Elemental means more damage from a Lava Burst instead of a LB, and Resto, cast a heal to potentially save someone while moving around. This ia an ability that is way underutilized by us and we should all look more into how we use it in raid fights Let me know here on when you usually use it and do you think its worth having.