Actually, UNC ran off 9 quick points in just over two minutes to start the 2nd half back on 1/12, but then SU went on a 16-2 run over the next 6 minutes with Joe in the game and Kadary still sitting. But then when Carolina went on their own 11-0 run (keyed by some bad, live-ball turnovers from both Joe and Buddy) JB made the switch to Kadary - which did stabilize the defense as you said. (That was actually a pretty crazy game of back-and-forth runs...)
My point is that the UNC game is a poor example of "JB mis-managed the minutes and cost Syracuse a W", which is the basic narrative that Matt Gutierrez was feeding with his tweets earlier this week. And I don't think that many (any?) of our other losses really fit well into that narrative, either.
And, yes - I do understand the difference between the box plus minus and the basic plus minus - but in this case, I thought that the fact that Kadary was -9 in the basic plus minus in the first half was pretty relevant to the discussion. And I don't know of a way to break out the box plus minus statistic into a first half number and a second half number. If there's a way to get that data, I'd love to see it.