Are the Steelers build to play catch up?

If the playoffs are realistic, the Steelers need to hit some big plays and stay on schedule. They're not built to play catch up. Can the Steelers win from playing behind? We hear what Matt Canada had to say about Najee Harris. Does he want more touches in the offense?? Crowley thinks Najee might be a problem. Dorin counters that almost EVERYONE wants their role expanded in the current offense. Mike Tomlin is breaking his usual norm and using two backs.