I delved into this right went I heard the news and now that I have had 24 hours to think about it I wanted to look at the loss of Bobby Frasor and how it much it will hurt?
First of all, the quantifiable stuff in the form of statistics. Frasor was playing 16 minutes per game shooting 34% from the field, 30% from three, while averaging 3.8 ppg. In 12 games he had 25 assists and 10 turnovers which boils down to a 2.5 TO/A ratio. Now in my mind the shooting stats mean very little. Frasor had not been shooting the ball particularly well and that was fine, obviously the offense was not suffering. He was often inserted at either guard slot and mostly played excellent defense as opposed to scoring a ton of points. The key stats were Frasor is concerned is the fact he puts in 16 minutes per game and when he does play the point he does so without committing turnovers for the most part. Frasor's A/TO is better than Ty Lawson's 2.0 and significantly better than Quentin Thomas' 1.1. One way of looking at it is through the first 12 games when Lawson went out and Frasor assumed the point there was a slight improvement when it came to taking care of the basketball. Now when UNC goes from Lawson to Thomas there is an obvious statistical drop off in the level of play at the point. The question is how well UNC can weather these situations with Lawson on the bench and Thomas has to be relied on to run the point and play good defense.
Ultimately the loss of Frasor cannot really be quantified beyond the apparent statistical aspects. The reason being it is difficult to know when Frasor will be missed because such instances with be situational and random. The expected situations of this type are Lawson resting or Lawson in foul trouble. The former is something there will be less and less of as the season progresses in the postseason. In fact I would not be surprised to see Lawson doing 35-36 minutes per game in March but to do that effectively he needs to not do it so much now so his legs are as fresh as possible come tournament time. The prospect of Lawson in foul trouble is a different animal altogether and might be the more prolific problem should it occur in a key game. Having Lawson saddled with early fouls and putting UNC in a position to use Thomas for extended periods could put the Heels in a hole that might be tough to climb out of against the wrong team.
On a general level this does hurt the depth and give Roy less flexibility. That may or may not be a problem. Looking at other key aspects, Frasor is a team leader and a guy that really makes everyone better just by the attitude and focus he brings. His defense cannot be underscored enough and it is nice to have a guard that can be brought in to play good defense on an opposing shooter. This is also the other side of the coin with exchange rate between Lawson and Frasor at point versus Lawson and Thomas. With Frasor you get solid offensive execution with good defense. Using Thomas more means a steeper drop off on offense and defense which again could be problematic in the wrong game. I also think not having Frasor could hurt if UNC needs to run a small lineup for defensive purposes as they did versus Nicholls State. If UNC faces a team in the Sweet Sixteen that employs three/four guards, not having Frasor as a defensive option in such a game could hurt. Then again there any number of scenarios where Frasor not being available is going to hurt, one could go mad exploring them all.
Having placed all of that fairly negative speculation on the table let me point out two things: (1) UNC won a national title in 2005 with an irreplaceable point guard who had Quentin Thomas as his sole backup and (2) Quentin Thomas is far more experienced and I think more capable than he was in 2005. By no means does this strike me as a major disaster despite the number of words I am writing on the subject. That being said, it is an issue that we will not know is an issue until it is actually happening. I think the greatest fear is the "1984 NCAA game versus Indiana" scenario where amid a win or go home contest a key player gets taken out by fouls(i.e. Michael Jordan with three fouls in the first half) and it is never compensated for by the personnel on the court. That is why winning the NCAA Tournament is so dang difficult because one bad game sends you packing. So I would venture to say that this torn ACL might mean very little for UNC until a the national semifinal when Lawson commits two quick fouls and UNC is forced to play 14 minutes of the first half with Thomas at the point where he fails to play at a level needed to win on that stage. Of course the Villanova game in 2005 was basically this scenario and UNC found a way to pull it out.
In the final analysis the answer to the above question is no one knows how much this will hurt. The rotation will work itself out and players will either step up to compensate or not. It is in a fan's nature to worry and in a blogger's nature to probe and speculate on the possibilities. Basically there is no way of knowing the impact until it actually occurs and if that is the case I would just as soon not worry about it too much. Or as my great grandfather used to say, "What will be, will be."