In a phone conversation, the encyclopedias author and IANTD founder Tom Mount reported that IANTD does not yet teach IWR because of its lack of broad acceptance. He includes a caveat that IWR is only to be done by qualified & properly equipped individuals in remote areas where a chamber is not readily available. When pressed for an example of such a location, he named Bikini, where chamber treatment could be 36 hours away. Fascinatingly, he mentioned performing the technique on about 15 divers over the years, including his wife during a trip a Roatan before a chamber was available there. His reported success rate is a startling 100%.
I don't want to sound like a cheerleader for IWR--I am not. However, I think this illustrates a problem with statistics on IWR, as I mentioned above. When someone does it in an emergency situation and it works, we never hear about it. We only hear about it when it doesn't work. That skews the performance statistics more than a little bit. I personally know of three attempts, although I was not physically present for any of them. All three were successful--and not reported except to the agency under whose instruction the incidents occurred. I do not know what they did with those reports, but I do know the agency was considering creating a course for it.
So far based on the information reported here, for the Libyan specific scenario where no 100% O2, properly trained divers or support personnel are available, IWR on air for divers who surface with DCS is, in the best scenario, useless and would actually cause more harm than good.
I would like to refer to what I just said for comparison. In the cases I mentioned, the treated divers had full face masks, oxygen, and a printed version of an established protocol (I believe Australian) ready to go when the symptoms began. That was not blind luck. The divers were in a remote area, and they knew they were very, very far from a chamber. They decided ahead of time that they would have those implements on hand in case they were needed. I dived many times there with those implements on hand, but we didn't need them when I was present. If I were diving in a remote location where I thought it might be possible that we would need to do IWR, I would try to make sure I had the equipment needed for it on hand.