Yes there is,
as a Warrior tank, even if Flash is added to skill list, the times they can activate it is very limited due to low MP pool
Overpower, their enmity generating AoE, usually for a few times at the start of each fights is essential to keep slept mobs from chasing the healer after enmity generated by heals during they're sleeping.
So for best result, learn / ask how many Overpower they're going to use, apply sleep afterwards.
But if the Warrior simply wake them up in the middle of a fight with Overpower... their fault.
