I once was playing Splinter Cell with a friend who, I have since learned but did not know at the time, had very little interest in stealth. To his credit, he did make an effort to be sneaky, but eventually gave up and ran through the level with a shotgun, shooting anyone he saw and yelling "STEALTHY! STEALTHY! STEALTHY!"
To his credit once again, he did beat the level with this strategy.