I always pull. That way I have immediate threat on everything, I don't have to burn my taunt, and the squishies don't have it from pulling. The only time I don't pull is if we have Michael(hunter) in our group, and his Misdirection is up. I don't utilize his Misdirection enough to be honest. It is quite wonderful, so if you have a hunter in the group that has it, use it. It puts all the threat from his first 3 shots onto whoever he targets with it(the tank hopefully). It is very nice to use on bosses to gain threat quickly so that dps can dig in faster. However, I do not have him use it if I am giving him a target to cc/ice trap on a multi mob pull because it is too hard for him to peel it off of me.
Michael has maxed his points in clever traps and trap mastery because we use him for cc quite a bit in our groups, and he does it well. When I give him a target to cc, he keeps that target until we get to it in our kill order. If it breaks, he re-traps it. He has complete control over his target and we do not worry about it unless the trap breaks early, and he calls out that it has. When that happens, he runs it to me, and I pick it up. That doesn't happen much though. Hunters can be used as a very viable cc source this way. The easiest mob for a hunter to put into his trap is a non-caster as it will run right to it. However, I do have Michael put a caster in his trap when needed, and he uses his silencing shot to do so. You have to have a hunter that has the silencing shot talent though, so be aware of that. If they don't, give them a non-caster.
We use sap as our cc when Steve is with us. It works well. When you have sap to utilize as cc, just put it in your kill order. Get the CC Watch mod so that you know when the sap is gonna break, and you can anticipate picking up your sap target. As you are tanking your mob or mobs, and you see that your sap is up, target the sap mob, and start moving towards it, as it will be going for the healer most likely. Just go to it and taunt it and put it in your threat gaining rotation. Everyone still stays with the kill order you are calling out, and you just add the sap in where you want it, depending on what type of mob you have chosen for the sap.
So, an example utilizing sap/ice trap would be, um, let's take one of the the sixs pull in Shadow Lab that is in the room with the second boss. Let's say the combo you have is a shadow priest(high dmg mind flay, must die first or just after the warlock pet or be cc'd), one acolyte(heals), warlock(high casting dmg) and warlock pet(dog this time, and they are demons, so no cc), a cultist(easy to pull into trap), and a deathsworn(easy to pull into trap, but hits hard, and can kill your hunter when re-trapping him if he gets a hit off on him).
Your group make up is a tank, healer, hunter, rogue, and feral druid. I mark the felhunter(dog) as the first kill target cause he dies quick and put the kitty druid on him, with the hunter. I make the shadow priest the second kill target and put the rogue on him and tell him to stun lock him. As soon as the dog is dead, the kitty and hunter switch to shadow priest and kill him quickly. The sap target will be the warlock. The ice trap target will be the cultist. Kill order will be felhunter, shadow priest, acolyte, warlock, deathsworn, and cultist.
I let the hunter know the path I will be taking to line of sight pull my targets to around the corner into the hallway so that they come directly to me. The hunter then knows where to place his trap so that I don't accidentally run the wrong mob into it. Sap goes on, and I pull by line of sight around the corner. Hunter peels his target off of me into his trap that is across the hall from where I am standing with my mobs to be tanked. Rogue immediately goes to the shadow priest and stuns and dps' it. Kitty immediately goes to the felhunter and begins to dps it. Hunter dps' felhunter as soon as his mob is trapped.
I pop bloodrage and do a Demo Shout on my mobs to initially keep them on me and off the healer when they are incoming. As soon as they are to me, I hit the first one with shield slam and revenge if it is up, I then target the next one and get a sunder on, then a T-clap to build more threat and slow their attacks on me; then cycle through them using tab with sunders/shield slams/revenge's, devastate when they reach 5 sunders, keeping T-clap on them and Demo shout when they wear off. I keep shield block up.
Dps moves to my acolyte that I am tanking after the shadow priest is dead. Sap will be incoming probably while acolyte is being killed or just after shadow priest is dead. I see it incoming, target it, move to it, taunt it and add it to my order. Dps group stays on acolyte until it is dead, then on to warlock, then deathsworn, then last is the cultist that has been kept ice trapped.
I have control over all the mobs and am calling out kill order as we go, to keep everyone clear on what is to be killed next. If I loose one and it goes for a dps or healer, they are instructed to run to me, to override their instinct to run for their lives away from me
If Michael calls out saying his trap has broken early, we run towards each other, I taunt it off of him, and put it in my order. If he is able to re-trap when his trap is available again, he does.
This is just an example, and can be modified to fit your group/style. Nothing is set in stone
Alot of this is just running the instances and learning the mobs and the classes and what they can do with their abilities. I have not played all the classes, so I ask questions of the other group members on what they can do, if I am not familiar with their abilities. I get alot of input from the group on the marking until I feel comfortable with an instance. We switch stuff around if it doesn't work well, until we can get something that does. It is all a team effort. I am still a noob warrior and learn stuff every day