John,
The 20' hose was just to irritate my brother. Btw, I tried a rig with the 7' long hose routing and found it comfortable. I screwed up on the "pony bit" as I recall the bungeed safe second.
I still prefer to hand off a (clear reg) rather than donate my primary, but that's because I'm old and trained that way. When I handed my octo to a rapidly ascending diver a few weeks ago, I felt it was the quickest/safest thing to do. It required nothing more than a quick grab of the octo, a quick purge with the mouthpiece held down while pushing it directly into his face (he'd spit out his reg on the bottom). I can only imagine the difficulty of doing that with my primary, especially one that was routed around my neck. With my left side routing, I was able to hand off to him in a "facing position" which I think (hope) he found reassuring.
Then again, I'm sure DIR (or Gooey or whatever) has a method of handling this rapid hand-off duriing ascent issue. I would certainly be willing to study the matter...I DO NOT like the fact that my gear is setup differently than most folks, although I like the logic of it. I agree that standardized gear does provide an added measure of safety, in certain situations.
That said, my brother is a great diver and most of the DIR divers I've met have been very skilled,albeit not very, er, 'friendly' or forgiving of my "less-than-right" ways. (I REALLY caught grief from a group of them once, after returning from a solo dive. What a group of jerks they were that day.).
I agree that the overall ratio of Jerks-to-Nicefolks is ought to be no higher than in sport diving in general, but my few encounters have run counter to this logic. They have been good divers, tho'.