Help how? They don't want you to report anything unless you're the one being insulted.
Building on the schoolyard analogy employed earlier, peer pressure works.
I know firsthand it works in the forums as well, as it worked in the CPU forum.
Remember that the point here is to figure out a way to give the community the tools it needs to maintain itself in the manner to which it wishes. Mods are one of those tools. The ability to pm one another is yet another tool. The ignore member feature is yet another tool.
So in this case the way to help is to be mediators yourselves, in the discussion as you see it going downhill before your very eyes as well as in pm's with both sides.
You don't need me to pm someone and ask them to chill out, or to pm someone and ask them to report the incident for which they were the recipient of a personal attack.
Mods are like traffic cops. We don't set the speed limits, the community does. We are tasked with enforcing the speed limits, but we can only do so much with the resources given to us by the same community that set the speed limit in the first place.
Does every person driving 26 mph in a 25 mph zone get a ticket? Pretty much never. Maybe if you are going 30 mph and the cop is having a slow day (reported post queue is low), but pretty much the traffic officer is going to manage his time while he is out on the beat so that he is available to catch the most egregious dangers to the community. The guy going 45 mph (or faster) in the 25 mph zone.
Give us the resources to put a cop on every corner, or a mod in every thread, and we'll be able to enforce the rules uniformly and consistently.
But give us a resource constricted environment and we are going to simply do the best we can to avoid descending into chaos and anarchy.
So do what you do now if you are on your front lawn and some jackass goes zooming down the street at 40 mph, wave your finger at them and let them know in no uncertain terms that their antics are not appreciated...but do it politely so as to avoid casting yourself as a rule breaker in the process. Two wrongs don't make a right.
By far the biggest help I can foresee the members doing is (1) watching their own posts to keep the convo to the high-road, (2) peer-pressure (public or privately communicated) to set expectations of members who might not be "getting it", and (3) contacting members who are being insulted to make sure they know they need to report the incident if the forums are to improve in a way that is manageable and sustainable.