Because Smith tore his ACL and missed the 2013 season, it required a look back to the 2012 season. Three games were watched -- the season-opener against the Redskins, a Week 5 matchup against the Chargers, and the season finale against the Panthers.
Alignment. In Steve Spagnuolo's 4-3 scheme, Smith almost always lined up at right defensive end. At times he reduced inside, usually in obvious passing situations, and he'd drop into coverage on a rare occasion. He stayed on the field on all three downs and was subbed out for a series every now and then.
Physicality and power stands out. Smith is a physical player who is more apt to win with power than elusiveness or diverse pass-rushing moves. He will initiate contact and has a good get-off. His size (282 pounds) presents an issue when matched up against tight ends as he uses his hands well to disengage (e.g. powering through Randy McMichael for a sack). He drew two obvious holding penalties in the three games watched.
Run defense struggled. Teams ran at Smith with some success. In fairness, this was a year in which the Saints' run defense struggled under Spagnuolo, who was replaced by Rob Ryan the following season. Smith's pad level seemed to rise on some plays, which helped blockers turn him. Smith's effort level was high as he regularly chased plays away from him.
How he could help New England. Smith would offer a different type of pass-rushing option for the Patriots because of his power, assuming his knee is recovered from a torn ACL that sidelined him last year. It's a bit of a different approach from the Patriots' other two top ends, Chandler Jones (longer and quicker off the edge) and Rob Ninkovich (high-motor technician). As initially projected, Smith would probably be best in a scaled-back role similar to what Andre Carter played in 2013, with his primary responsibility to play forward in a pass-rushing role. His presence would also provide flexibility to move Jones inside in passing situations, which the Patriots did with some success last year.