Originally posted by Xars
Rushing: Pancake Chef is really good, but you need to win the block roll for it to fire. If you're a Pure Run OT on a Pure Run O, go for it (and get a really high Run Block Tech skill value). If you're a Balanced OT in a Balanced O, it won't fire as much and you should probably consider other SA's depending on your RBT skill value and the goal of your team's O. If you have a high Run Block Power skill value, you may want to consider Unstoppable Force because that fires when you are losing the block roll.
Disagree on the balanced team. I think Pancake Chef is really good if you run the ball, regardless if you're a Pure Run O or not. You will probably have slightly less RBT and RBP on a balanced OT - but your opponent is likely not running pure run-stopping DEs or anything either. In fact, in the current meta, more DEs are built to stop the pass as opposed to the run.
When you say Unstoppable Force you mean Immovable Object, right? I've never used it so I won't comment although just based on my understanding of how the skill works, I'm not a huge fan.
EDIT: I will add though that obviously, as you noted, depends on how much running the team wants to do. If you're only running 10 - 15% of the time then obviously it's not particularly valuable (although I wouldn't call that a balanced team) - but on that note then Immovable Object is not particularly valuable either.