Is this even remotely surprising?
What it does suggest, though, is both Wallace and offensive coordinator Todd Haley came in prepared for Wallace's return, and both are comfortable enough with his understanding of the playbook to be on the field in the team's first meaningful game of the 2012 season.
The first team offense didn't attack deep very often, but when it did, it was to WR Emmanuel Sanders, Wallace's temporary replacement, and it came from the offensive right. That's the side of the field from which Wallace took a Ben Roethlisberger pass and sprinted for a 95-yard touchdown against Arizona in Week 7 of 2011. It's also the same spot from which Roethlisberger floated a duck to Wallace against Denver in the playoffs last year. Wallace hauled it in, and it was initially ruled a catch, but was overturned correctly upon replay.
A healthy Roethlisberger hits that pass, and the Steelers score on that play. Life moves on, and with it, a healthy Roethlisberger looks to get it back in Week 1.
Wallace probably does, too, and it seems he has a strong enough understanding of the offense to give it a shot in Week 1.