By contrast, look at DREAM in Japan, which held over the round structure from PRIDE Fighting Championships: a 10-minute first round followed by a 5 minute second round. This sort of round structure puts an emphasis on conditioning; the fighters have to fight two consecutive UFC rounds without a break. That's more openings for strikers to get past a wearying defense and a long time to be fighting off submission attempts or having to maintain guard. (DREAM judges fights on their entirety, so neither round is weighted.)
How do officials determine when to stop a fight?
This is, by far, the toughest job officials have and the one they're most criticized for. A fight stopped too early ires the fans and incenses the losing fighter. But a fight stopped too late is even worse, a hazard to the competitor's health.
A doctor can stop a fight if a fighter appears too injured to continue. A corner can stop the fight by throwing in the towel for any reason. Tapouts and unconsciousness are relatively easy to spot. The tough calls come outside those lines; the standard is when the opponent is "unable to intelligently defend themselves".
Obviously, that's quite a judgment call. Usually, the fighter in trouble will be attempting to protect themselves from strikes, so pay close attention: how many strikes are landing clean? If the fighter is lying there, taking shots through their shell, they had better escape quickly or the fight will be stopped. But simply turtling, even if effective, will likely draw a stoppage anyway. The fighter in trouble wants to be trying to improve their position: escaping from under a mount, reversing position in the ring, or getting back to their feet.
Eventually, though, the decision is in the hands of the official and some have a quicker trigger than others. Watch enough fights and you'll start to know, instinctively, if the stoppage was on time.
What should I look for when I'm trying to score a round at home?
Round scoring at home is a valuable exercise. Not only will it help you anticipate the decision, it'll help you understand the fighter's mindset round-by-round. A fighter down two rounds in a three round fight knows he has to finish it then to have a chance at winning.