I would always lure if it is an easy CC position. Takes one more variable out of the equation. Also if your chosen attacking point is on the opposite side of the base to the CC you risk the CC troops spreading out too much for poison to take them all and you can end up all meeting at the core and a messy fail. At best it will distract your troops and make the attack more risky than it needed to be.
My view is that if I don't lure I always allow a rage for when the two sets of troops meet. As above I also try to hit the CC troops head on so we dont meet right in the heart of the base where the defences are crazy hard.