A guild on our server does this exact thing to influence this. They have everyone stand behind walker with one tank, and that tank guards the tank that stands out and picks up the warriors. All of the trenchcutters run to the other tank.
They place the guard on the OT as they're killing the last droid.
Close. We actually have the healers run around with the OT as well. Doing so means both warriors in the first pack can be picked up instantly (healer grabs one, tank the other). It ensures there's no risk of the OT outranging the healers. Finally, the warriors in packs two and three usually switch targets to the healers before they reach the group behind the walker (gutters do not switch to the healers, don't ask me why. An unlisted effect of the shields?), so if the OT ****s up and misses one of the warriors it's not the end of the world.
I've seen reports claiming that if the tank picking up the warriors is a Shadow this won't work, because the healing threat they generate, even while guarded, will be sufficient to cause the gutters to switch targets.
That's on 8-man. I've no idea how it would need to change for 16-man.