Forcing teams to go one on one in the post is usually a pretty decent strategy. Post-ups are typically not the most efficient way to get good shots.
Also, there is the matter of trade offs. If you double the post, you can prevent post-ups, but it puts your defense in rotation and can give up open 3s. We rarely double the post, which does leave our bigs isolated. In some cases, like Lynn Kidd from Miami, you risk losing the battle so that you can win the war. Kidd scored 20 on us, but he did so in part by shooting 11 midrange jumpers. I know I'm a broken record on this, but forcing midrange jumpers is one of the most important things we can do on defense. Meanwhile, we were able to shut off the rest of Miami's offense and had a nice defensive outing despite what Kidd did.
Now, there is a good point above about how our switch-heavy defense can make the trade offs different. For the most part, we haven't gotten burned too often with guards switched on bigs, but Clemson was able to hurt us. Switching is a no-brainer against lightweight teams like UNC, but against a team with multiple post scorers, it's a tougher call. I imagine we'll do some things differently if we face Clemson in the ACCT. Also, I think it really hurt not to have Mason Gillis on Saturday. Of our wings, he's the best at defending bigger players.