Most people here aren't questioning that shooting, moving, playing tight are important, much like form, speed, and strength are important in other professional sports, but you get to a level at which most players on any given team are at about the same skill level, where players need to be able to communicate to tip the scales in their favor. If 2 teams of 5 equivalant players faced off, the wins would be split fairly evenly, but once one team starts communicating, one team has 5 decent players that are able to draw on a little support when they need it to avoid being eliminated.
Of course, its really not fair to limit the scenario to players that are incapable of communicating at all, or of moving, shooting, etc. The truth is that all players have at least some ability in each of these areas, some are better shooters, and some are better talkers, and when the players that talk well are able to raise their other skills to a decent level, they will decimate players that focus on individual skills.
Deep down, humans are social animals, we like to communicate, and as a result, we develop group skills that enhance our individual skills, thats all communication in paintball is, an enhancment of the players individual skills by the player borrowing the abilities of another (others) for a few moments.
