My Heroic Strike crits are averaging about 1800-2000 more than melee crits, self-buffed. I am wondering about the feasibility of using piercing howl during free gcd's rather than rend for bonus Heroic Strike damage.

If Heroic Strike's 495 bonus damage is translated into 2000 actual damage after attack power bonus, then a dazed target will take ~700 bonus damage from Heroic Strike (35% more vs dazed target), and more when raid buffed.

You will also be buffing hunter's steady shots as a side bonus.

After some testing, the bonus damage on heroic strike from piercing howl's daze effect does not seem to be modified by attack power. I am getting ~+200 damage from it