what about that in the SSI instructor manual the donation of the primary is specified as "preferred"
It seems to me is a way of teaching to look at each others equipment and discuss about the techniques to use, before the dive.
the different detail: i came up with a discussion about the primary donation with a colleague few days ago... i was pointing out that in general in the rescue courses we are teaching to always stay away, and keep distance from someone panicked... even if he's drowning. 'cause the first rule is "protect yourself" and... then... help.
the donation of the primary, in his opinion, goes against this principle... letting a panicked diver take the only, surely operative reg, out of his mouth. leaving both for few seconds (hopefully) without any gas and with being also uncertain about the alternative source.
but is also true that if you do that... and the alternative is not working... then you're quite screwed yourself
you are correct that ssi does "prefer" we teach donating the primary. at our shop we do not. first, because our boss completely disagrees with this method. and second, because the regs are not configured to do it properly. this is a whole other discussion.
i completely agree, as would anyone, that the key is to discuss these things with your buddy or team before the dive so everyone knows how to deal with it. then it should be rehearsed prior to descending.
very interesting point about putting yourself first in a rescue situation. and i agree in principal with this. however, in an out of gas situation are we really going to sit back and wait for them to pass out or bolt to the surface before we step in ? i think as a buddy, and certainly as a dive pro, you have agreed to help as soon as you agreed to go diving. it is required for a dive pro to go above and beyond to give assistance. and i would hope other non pro divers understand that when you agree to accept the responsibility of being a dive buddy you also agree to provide gas immediately should the need arise.
lastly......i think more divers should pay better attention to their alternate air source. it should be of high quality and maintained just as well as your primary. not just some piece of crap that hangs there just so you can say you have one. it should be tested once your gear is assembled and again when in the water before descent just like all your other gear. so personally i find this argument (which is mentioned all the time) invalid.