My personal reason for wanting 2 hoses & 2 orifices & 2 nozzle bodies is to preclude total row blockage. The orifices just have a small hole in them. A speck of rust can lodge & block them. We see it occasionally on sprayer tips. Filters are much better today than 45 years ago....but stuff still happens. Using 2 separate nozzle bodies, orifices, and hoses would lessen the chance of totally starving 1 unit. The nozzle bodies are already on sprayers, therefore you'd only need 1 additional orifice & a few feet of hose. If anyone is considering using them in "skip-row" configuration, redundancy would be even more important.

I think it's a "here" thing.