Carter-Williams played a solid game last night, and it's pretty clear (to me, at least) that this team lives or dies on his play. Last night he didn't score much but 8 assists and 1 turnover is exactly the kind of night you're hoping for from your point guard.
We all know MCW has been struggling for the past few weeks as SU got into Big East play. Some of that can be attributed to better defenses keying on him. Some of that can be attributed to teams having more film on a guy that barely played at all last year.
One factor that I think hasn't been talked about enough is the fact that the primary benefactor of his assists is no longer on the court.
Before Southerland's eligibility issue, MCW was averaging 9.6 assists and 3.6 turnovers per game (through 16 games). Since Southerland's absence, MCW is averaging 5.8 assists and 3.8 turnovers. The most assists he's had in that span (8, last night) is less than he was averaging before. Meanwhile, the turnovers have stayed around the same rate, though they are a lot harder to stomach with around four fewer assists per game.
Luke Winn did a great job of breaking down MCW's assist statistics back in early January before Southerland's absence. In 14 games, Southerland received 34 MCW assits, the largest number on the team to that point. That averages out to 2.4 assists per game (and at an average of 2.5 points per assist, it adds to around 6 points per game).
Obviously you can't just say if Southerland comes back MCW will start averaging an additional 2.4 assists per game (getting him back to a fantastic 8.2 assists per game), but it's clear his absence is having a direct effect on the point guard. In addition to the missed offense, teams are packing it in on Carter-Williams, limiting his driving lanes and daring him to shoot threes over them. With Southerland on the court, the defenses need to respect an outside shooter, making it easier for a point guard to penetrate and dish (which is MCW's strength).
The point is, we need Southerland back for so many reasons besides just his scoring. His presence on the court changes Syracuse's offense dramatically.