The problem is Icy-viens doesn't change the instant there is a buff or nerf. All these sims I am seeing is saying that Barrage isn't worth using compared to crows for ST and Volley is better for MT.
In last nights raid I tried Both Barrage and Volley, and Volley Did a million times better in AOE situations than barrage. I was actually breaking a million DPS on trash pulls with Volley and was around maybe 800k dps with Barrage.
Granted, my stats are not ideal, i can't seem to pass 19% mastery so my numbers will definitely be lower compared to others.