DA Aquamaster:
In 20 years of diving with Mk 10's in an area where Mk 10's are very common and see hard service in cold and dirty conditions, I have never seen a Mk 10 swivel or swivel o-ring fail nor have I even heard of one failing.
Good points DA Aquamaster and I admit that this particular issue is a minute detail that some DIR advocates and players do not fully agree on.
As far as the failure issue goes, I guess it just depends on who you ask, but in my only 18 years of diving I have seen them fail. I have seen brands other than SP have the swivel/turrets fail. I used to see it more when I worked on the bench servicing the regs. I have to admit I have never seen it become life threatening, but I can say w/confidence that it pissed off the owners. I also will admit that it does not happen often. By that same token I have
never seen a non swivel/turret style reg fail at the turret
. For me, I'll live w/o the swivel and remove the headache. In my DIR courses, when asked, I will advise leaving the turret reg in the shop's showcase and thus removing one potential failure point.
Speaking for myself, I am not motivated by anything other than to simplify diving and to teach DIR as I have been taught to do so and as I understand it. To that extent, yes I am a minimalist and I do not advocate using any piece of equipment that does not simplify diving and allow the diver to concentrate on enjoying the actual dive instead of maintaining (needless) equipment that has potential to fail. I will always advise removing the potential to fail so long as it is w/o any detriment to the diving experience.
All this being said, sure there are many DIR advocates and even some of the big name players using regs w/a turret, but if you want an answer that fits into the philosphy of the system, remove the potential failure points that are not necessary to the diving. The swivel is a nice "extra" that accomodates hose routing, that's all. For some that is worth the small risk of the failure. Others feel that the hose has less potential to fail if bent than turret.
I am only answering the original question as to whether it fits into the DIR system philosphy. And as I said earlier, as I understand it and as I teach it, the swivels do not present enough of a benefit to hose routing to advocate using them vs. a non swivel with a good routing platform.
FWIW. I wouldn't get too caught up in this Internet hoopla...remove the label and DIR is just a system of removing the BS and getting down to diving safer and thus more enjoyably. If you feel more comfortable w/a swivel, have at it, it doesn't make you a bad person and is not a game ender for being "DIR" if that is a concern. I was only answering the question as I would have answered any student in my class. Like I said, there are many players that are DIR that use regs w/turrets, and this only goes to show one how small a part the equipment lays in the big picture.
dive safe!!---brandon