You pretty much have to stress the deterrence effect of OC if debating tactics. A few other positives come to mind such as you have an easier draw and can carry a bigger, more effective sidearm with less hassle. Many CCers carry the popular .380 caliber pocket pistols, so they are giving up effectiveness in exchange for conceability. I've seen someone put it this way "CC gives you surprise, but OC gives you deterrence, effectiveness and education".
Perhaps its a wash, but I prefer OC for its educational benefits which CC can never provide and as such I believe that OC ultimately furthers gun rights, which itself is a good thing in that it has an overall downward pressure on crime and positive influence on liberty.