I still have no idea why they didn't just put Leftwich on I.R., and kept Hoyer on the roster last year. That was truly dumb.
Per Ed Bouchette:
The quarterback the Steelers really wanted was Brian Hoyer and they let him slip through their hands. If Arizona had not put a second-round tender on him as an RFA, the Steelers were going to try to sign him. However, they had him on their team when they signed him Nov. 20 to the 53-man roster after the injuries to Ben Roethlisberger and Byron Leftwich. They released him on Dec. 8 so they could add josh Victorian from the practice squad. That was a mistake, and they know it. Bruce Arians also must have known how much they wanted him back by placing the second-round tender on him. Hoyer signed that tender this week.