Trace broached (in post 167) what should be the primary topic in this discussion - the potential for ambiguity within and between standards, in particularly between cave, decompression and mixed gas standards in the cave and tech communities. The cave community, and NACD and NSS-CDS in general seem to be a bit out of step with the rest of the world when it comes to mixed gas and decompression procedures and some of the standards and practices seem to have a "legacy" feel to them.
Marci has commented on her preference to learn AN/DP prior to taking (full) Cave. It was a wise choice as while NACD seems to assume that "solving decompression problems" is a focus in the 4 day, 8 dive full cave course, some agencies that teach AN/DP devote a full 6 dives to teaching AN/DP with 2 of those dives being preparatory and 4 dives being actual decompression dives. Obviously, in an 8 dive Cave course, somethings going to get covered very lightly and those things are the use of a high percentage deco gas and the specific decompression aspects involved in diving in a cave at that level. In fact, in the majority of (full) Cave classes, it appears that decompression is just something that gets done in the course, it isn't really taught in any meaningful sense of the word. And given that switching to the wrong gas is still the largest single killer of cave and technical divers, that seems to be a very unfortunate situation.
In that regard I fully supported Marci taking AN/DP at the Intro to Cave level. In fact, given that I had taken AN/DP in an offshore soft overhead environment, I saw a great deal of value in taking it again in a cave environment.
As Marci has related, one of the dives was to Hendleys Castle to a maximum depth of 150' - essentially inside Hendleys Castle just past the sand slide which is at 135 ft. This dive was also of interest as it was taught using a stage for the combined travel gas and first deco gas (32%), along with 100% O2 left in the cavern with the bottom mix of 25% as back gas. In essence, we were not only covering AN/DP, but also the gas planning, bottle handling, dropping and retrieving aspects of stage diving in a cave - at the Intro to Cave level.
The other dive of note in this combined AN/DP course was to Lower (lower) Orange grove, again to a planned max depth of 150', past the start of the goal line, but short of the dip to 170'. We did not get that deep due to turning the dive on our planned time, but it would have been considered acceptable to go to 150'.
Where this relates to the current drama surrounding standards violations is that our AN/DP, as a non-NACD class, with NACD Intro to Cave certified students, was taught by a long standing NACD instructor trainer, board member and past president. His view was that taking us on a jump in Hendlys, one level above our existing NACD certification, was allowable and that doing so to 150 ft with appropriate MOD gasses (25%, 32% and 100%) was also appropriate, given the straight forward nature of the dives in question. There is of course the issue of an END below 130 ft, but that was also a part of the learning experience in the AN/DP class. Many instructors now teach AN/DP like many instructors used to teach Extended Range classes - with an eye to demonstrating to the student why an END deeper than 130 ft is a bad idea.
That is the ethical dilemma posed when mixing cave training with technical training involving mixes intended for use below 130'. An instructor could choose to do the training with a depth limit of 130 ft, but in so doing they would be missing one of the more important aspects of the training and they would be certifying a student to die to 150' when the student has in fact never been there in a supervised setting and may have no idea how much difference that extra 20' can create.
Now, I bring up this issue of "ethical dilemma" as most professions where ethical dilemmas occur have procedures fro addressing those dilemmas. A dilemma arises when you are confronted with a situation where either approach you choose either has a downside, or places on rule or standard in conflict with another. When that happens, a problem solving model is used to prioritize the issues that are more important and determine the best approach. The models will balance various ethical tenets to find the right balance between rigid adherence to rules, and accomplishing what needs to get done in a safe and effective manner.
What I have picked up over my years interacting with the cave community is that many very good instructors intuitively understand the dilemmas involved, and that most instructors operate in this manner, applying some common sense approaches to balancing conflicting standards while delivering effective training in a safe manner.
However, it's equally obvious that given the lack of recognition of the existence of conflicts between standards (both internal and external) by some training agencies, and in this case NACD in particular, instructors who are acting in a profession and ethical manner are placing themselves at risk of being accused of a "standards violation". An important point to note is that acting "ethically" does not mean rigidly adhering to standards, but instead means using a solid and accepted process to balance conflicting requirements to reach a solution that allows the instructor to conduct the required training safely and effectively.
The irony here of course is having a discussion of "ethics" in the context of a cave diving training agency. I'm not seeing much of that here, by any definition of th word ethics. A training agency, the same agency that should be aware of, acknowledge and prescribe a valid process for resolving the ethical dilemmas created by it's standards and with accepted technical dive training practices, is instead busy prosecuting an investigation against an instructor who is doing nothing more than a number of instructors have done over the years. I'm not going to throw the instructor who taught us AN/DP at Hendleys and Lowe (lower) Orange Grove under the bus in the thread by giving a name, but he's never hidden the fact that he teaches this class in those areas, he's been doing it for well over a decade, and he's proud of the fact that none of the hundreds of cave divers he has trained as ever died as a result of cave diving.
At the end of the day, that's the measure that matters most, and any risk that was taken in class to demonstrate the risk of an extra 20' in END obviously seems to be more than made up for by cave divers who move forward with a healthy respect for the need for an END in a cave shallower than 130 ft. Based on our experiences in that class, as well as in trimix taught by another instructor (at the full cave level) in those same areas, we consider 100' to be the max END for our team.
What bothers me most with this issue is the disparate nature of the complaint against Rob Neto, and the lack of consideration, or even understanding of the inherent conflicts and the role that a meaningful standard of ethics including an ethical problem solving model should play in cave training.