Well I don’t know after all I haven’t been blessed with the kneeling to the SCUBA god but , even though I was a paramedic, National Registry EMT-P, and Instructor Coordinator in Michigan, tech deep, trimix, advanced deco certified, advanced nitrox, rescue diver and a whole host of other certs that make my fingers cramp to type all out. I can’t remember for the life of me ANY training agency or instructor that would advocate crossing hoses. Seems to me that could get awfully confusing in an underwater situation. I keep everything the same between my single and double tank rigs, for the simple facts that everything is VERY streamlined and easy to get to. And oh yeah about four training agencies suggest something similar so maybe when I come to rescue someone that person might not get confused. But then again I’m not an instructor so I wouldn’t know any better than some SCUBA god on here that makes you dance to his whim just to be one of his buddies. All I KNOW is that if someone, no matter how I dove, cut MY air line they’d have a LOT more to worry about then who they select for buddies or how their gear was set up.