This past Saturday I went to the field with my paintball team. I was unable to play, but I watched. One of the games I was spectating had two superb examples of paintball-as-gunfight-training.They happened almost simultaneously.
The first came from one of the miscellaneous players on the team my teammates were on. He wasn't one of them, but he seemed quite a capable player. He ran up to a bunker, an old bumper car I believe. He had a good commanding view of the battlefield, but was vulnerable. The enemy was pushing up, and from his post he had to hold down 3 separate avenues of attack by himself. Through quick bursts of suppressing fire, he pinned down the enemy from all of these posts. Even a player who attempted to get the drop on him with maneuver warfare fell to his gun. Despite being outnumbered by similarly armed opponents, with good cover he was able to hold his position.
But that player is the other proof of training. He was a magfed player, running a replica AR-15 feeding from magazines of unknown capacity (between 10 and 20 is standard for them). He charged, firing, only to have his gun run empty. Without missing a beat, the paintball pistol at his hip was brought into play. I'd be surprised if his fire lapsed for more than a third of a second, from running empty (paintball guns have a much different sound when empty) to resuming firing with his handgun. The transition to sidearm was a thing of beauty, really.
I wish I had had my action camera handy, not only did I miss this exchange, but I missed one of the best comedy pratfalls I've ever seen. It was my best friend, rival, and team captain, who misinterpreted the start countdown and took off, only to try to stop and begin sliding. Arms and legs flailing, he slid 5 feet down a snowy hill before a beautifully executed banana-peel style fall.