What is a one-sentence summary of the following article?
Bringing up old problems or other similar situations muddies the water and makes it even harder to safely wade out. Make an effort to only discuss the current problem. If one of you brings up something from the past, the other can say something like, “Let's focus on the problem in front of us first, okay?” After reducing tension and getting perspective, the final knockout punch for ending an argument is finding a solution. To be sure that happens quickly and without rehashing the whole issue, set a timer. Set the timer for 20 or 30 minutes and aim to resolve things by then. Anger can cloud your ability to see the real issue at hand. Often, there are other feelings lurking beneath that anger. Try to name and own what you're really feeling with “I” statements.  For example, anger might provoke you to say harsh things, like “You're so insensitive. You don't care about how your actions affect me.” Reframe that with an “I” statement like, “I feel ignored. I would appreciate it if you considered how the things you do affect me.” All arguments can't end with each person getting their way. Both parties have to be willing to make some concessions for the greater good. This requires flexibility.  Ask yourself whether the issue is really all that important to you. Will it matter in 5 years? If not, you might agree to disagree or concede if the issue is actually important to the other person. For example, if you and your coworker are disagreeing over who will lead a presentation, question whether you really care. If not, let them lead or agree that they will do it this time and you will lead next time.

Summary:
Stick to the issue at hand. Set a timer. Get real about your feelings using “I” statements. Be flexible.