The Bose configuration is intended to widen high frequency horizontal dispersion. They did it that way instead of the right way, which is to use tweeters rather than just midbasses alone.
That's true of large arrays, 3 meters or more high. With shorter arrays the main benefit is the reduction of the vertical dispersion angle, especially in the high frequencies. This sends more energy to the audience where you want it, less to the floor and ceiling where you don't. The result is much cleaner sound, especially in acoustically poor environments, which is probably 95% of the clubs we play. Even a short array of tweeters only 40cm high can work much better than the typical point source horn used in most PA speakers.