Any absolute that says less components in the signal pass is better than more(higher order) is dead wrong IMO.
You can see an example as to why less components can be a bad thing even in a 2 way bookshelf speaker shown below
http://www.salksound.com/wp/?p=135High order crossovers can be really beneficial especially in a floorstander speaker. In a multi-drive speaker high order crossovers are beneficial because you can really fine tune what frequencies the bass, midrange and tweeter play. This is very important for allowing the speaker to have a great on-off axis response,low distortion, dynamic capability with low compression. All the really important stuff as to why you use multiple drivers. Also controlling what the drivers play prevents the speakers impedance from dropping drastically low which would put electronics into shutdown. Steeper roll-offs can really control non-linear distortion like cone-break up which all drivers suffer from but at different frequencies depending on the cone material. One of the main causes of listener fatigue.
