Ignoring for the moment that Many bosses are immune to daze effects.
And using the following values:
Steady Shot is 35% of your damage.
Steady Shot hits for 700 damage for you.
Having a mob dazed would increase your Steady shot damage by 20%(based on a base extra 175 damage according to wowWiki).
If a mob was dazed 100% of the time your dps would increase by 8.59%
If a mob was dazed 9.6% of the time(my estimate on how much Concussive Barrage would keep a single mob dazed) then your dps would increase by .73%
-The Rogue Combat Talent Blade Twisting gives the rogue a 10%/20% to daze a target for 8 seconds when using their Sinister Strike, Backstab, Gouge or Shiv abilities.
-A Paladin's Avenger's Shield, acquired by talent, "dazes" 3 targets.
-Mages have the talent-trained Blast Wave which dazes all enemies in an area.
-Hunters have Concussive Shot, which dazes the target for 4 seconds, and a talent in their Marksmanship tree called Concussive Barrage which grants their auto-shot attack a 2%/4%/6% chance to daze their target for 4 sec.
-Warlocks have Aftermath which gives their Destruction spells a 2%-10% chance to daze for 5 sec.
-Warriors who have Rank 4 Shield Bash can also daze for 6 seconds, and warriors with Piercing Howl can daze all nearby enemies for 6 seconds.
Now concussive shot is a bad idea because it will make the hunter go OOM very quickly with very little reward. Not sure about the others.
The basic idea here is that there might be an un-tapped resource for boosting the over all raid dps if your raid had several BM hunters(who I belive use Steady shot more than the others do). What I'm not sure of is how much trying to keep daze up would lower each classes' dps...and if the amount lowered would be more or less than the BM dps raised.
Anyways I thought this was good enough for a blog post.