Not only are the standards for instruction, but also for the dive professionals operating under that agency, no? And oftentimes dive centers are even more strict than the agencies (in, for instance, requiring certain specialties).
So, in one hand, we have people saying that beyond instruction divers can forget the limits, on the other hand there are stupidly strict dive centers. I guess it depends on what gives them more money...
And isn't there a conflict between training and what is said and practice afterwards? Simple overheads are fine? How about proper caves? Why aren't those ok? Or trimix? What's the need for an OW diver to do any more training? In many threads we read users saying "You shouldn't be doing that dive", "Get training" and now it seems to be "The limits are recommendations". Seems a very weak position.
And your view is very US-centric. In many other countries there are laws for diving that require certification and where divers are indeed limited to their certification standards.
Even where there are no laws, does it make sense not to try to set some rules, which are directly related to what has been taught to the students? There may not be scuba police and people are free to kill themselves whatever way they want, but should we think that's fine?
As with most things scuba, the answer to most of your questions would be "it depends". Diving is very circumstantial ... environments, people, agencies, and just about everything else associated with the activity differs depending on who you're talking about and where they're diving. That's why so much of the information provided on ScubaBoard ... or even in a typical dive class ... can't be universally applied.
I don't believe that, as a dive professional, I'm under any obligation outside of classes to "operate under that agency" ... that agency tells me how to structure my classes in a way that not only provides a safe environment but covers me from a liability perspective. The agency tells me how and what I can teach as a representative of the agency ... but they're not my parent, and when I'm diving on my own time I'll make my own decisions about what's appropriate. As an example, my agency is quite adamant about "no solo diving" ... no exceptions in their standards. And yet I solo dive quite a lot ... I just don't do it in class, and don't promote it to my students. For those who are curious about it, I'll explain that there are agencies out there with different philosophies and recommend that they seek out those classes or learn it as I did ... through technical training that goes into far more depth on issues of redundancy, dive planning, gas management, and situational awareness than the recreational solo classes do.
I don't see as many conflicts as a lot of people involved in most of this type of discussion on ScubaBoard ... because I don't live by or profess to hard rules for scuba diving. What I try to instill in my students is that diving is all about making good decisions, using common sense, and keeping a realistic perspective on your own abilities. People who do that are able to look at changing situations and make decisions that will avoid most problems, and manage the ones they can't avoid before they become unmanageable. I won't give my students hard rules like "stay out of overheads without proper training" ... I'll explain to them why I think it's a really bad idea and assume that they're smart enough to decide for themselves how much risk they want to take ... if they can't handle making reasonable decisions, then they don't belong on scuba gear ... and I'm not signing on as a nanny. When you read posts with lines like "You shouldn't be doing that dive" or "Get training", it's usually the results of something someone posted that clearly indicates someone is doing something without having considered the risks ... or is completely ignorant of what those risks are. It's often easier to make those comments than to explain why ... or more often than not, those of us who try to explain why invariably have our posts picked apart by someone who just can't resist picking six words out of a lengthy post and making it out to seem something that was never said in an effort to make themselves look more knowledgeable. Such posts invariably descend into the realm of the absurd, and usually cause those of us trying to be helpful to just decide that it's not worth our time to attempt to continue the conversation. I see this very thread heading off in that direction ... as most in this forum usually do.
Yes, I know my view is very US-centric ... that's where I teach, that's where I do most of my diving, and therefore that's the perspective I can mostly contribute to the conversation. Thanks for pointing out the obvious. I've been to the Maldives, have so far managed to avoid the Caymans, and won't even consider diving in France ... three nations that are famous for their governmental interference in diving decisions. But in fact there are also places in the USA where local governments pass laws that interfere with what should be a person's personal decisions ... like the attempts in Laguna a few years ago to mandate buddies and snorkels ... both laws caused many people to stop going there, and eventually the merchants who were losing money as a result convinced their local officials to drop those silly ordinances.
No, I do not think it's fine that people sometimes make poor diving decisions that result in tragic outcomes ... but I think the notion of some government entity or diving agency managing everyone else's dive plan for them is an even worse alternative. When scuba diving as an activity reaches the point where some bureaucrat decides how I should dive, I'll stop diving and take up some other activity that gives me the freedom to exercise personal responsibility and live (or not) with the consequences of my decisions. I don't need or want someone else assuming the role of protecting me from myself ... nor would I find that a very attractive way to train other divers. Diving competence is defined as much by a diver's ability to take responsibility for their own safety as it is the physical skills that are learned in a classroom. That's a point that isn't emphasized enough in a lot of classes ... and for which I attribute primarily to the abysmally low standards that allow someone to become an instructor while they still barely know how to dive.
There's way more to diving than what's "in the book" ... whether that's the student materials or the agency standards we're considering. You can't learn what you don't know as long as you're willing (or forced) to just blindly apply rules of thumb without understanding why those rules exist in the first place. And a big part of that understanding comes from knowing when the application of that rule doesn't really make much sense. "The limits are recommendations" isn't a weak position at all ... it's a jump-off point to the most important question in all of scuba diving ...
"Why?"
... Bob (Grateful Diver)