Please, have grab your coffee and have a seat. I expect this will be long.
I suspect that my courses are more rigorous than most. For open water, I never allow students to spend time on the knees, and I work hard to ensure that they carry minimal weight as that makes all the difference between in them controlling their depth. They also come out fairly proficient at frog kicks.
So my students always have a solid foundation (don't ask me, don't ask my students even, ask the experienced divers who dive with my former students). For new students that trained under other people, I require a separate evaluation fun dive. I'm not going to have them take a course from me where they do not have the necessary skillset to learn the skills involved with whatever course in which they are interested in. I need to ensure that they don't need remedial training. And at the end of the fun dive, at the safety stop, I'm going to have them drain their cylinders to 500 psi and see if they are properly weighted as the final check.
The best skills course I've taken has been hands down GUE fundies. I could be wrong, but I can't imagine someone earning a rec pass having fear in the water due to a lack of skills. For any certified diver, if they have fears due to a lack of skills, then their past instructors took their money, violated standards, and in my opinion, ripped them off.
The mainstream industry is rife with check box instructors. Back when I was teaching for a shop, I shared the pool with a PADI IDC Staff Instructor teaching DM candidates. I was teaching OW. All my students were never placed on their knees. After they finished the standard float/swim test, we did the skin diving skills. Then we moved onto scuba skills and everyone was separately weighted by me so that they were floating midwater/trim. The DMC were firmly planted on their knees for most of the time.
My students and my assistants thought they were all remedial open water students. The look of shock on their faces when I told them that those were divemaster candidates becoming professional divers still makes me laugh.
And this IDC Staff Instructor can't use a compass to save his life.
So yes, when statistically when you choose a random instructor from a mainstream agency, you are not going to get much. When you take a course, do you have a discussion of what you are going to learn? I've never had a student ask me that. However, because I teach for SDI and they encourage instructors to exceed minimal standards in meaningful/appropriate ways, I have written for each one of my courses an addendum to the SDI syllabus, because I will teach meaningful classes.
If someone came to me to take a night/limited viz course, I'd do a fun dive to evaluate their skills. If they needed work, I'd steer them to my Advanced Buoyancy Course that is very much GUE fundies like. Or I'd send them to take GUE fundies at a 8, a local dive shop that teaches NAUI/GUE courses. If it was simply that they were afraid of not being able to see, then I'd recommend to take my night/limited viz combined with navigation course that I only teach during peak algae blooms in May. I teach that 1:1, and you will come out of it with solid navigation skills as you are going to be given a map to navigate in the soup and at night in the soup as well as other exercises.
So it comes down to agency and instructor. I think the performance requirements for most certification in mainstream agencies to be insufficient to be meaningful. That's where agency comes in. I recommend going with ones that either have high performance requirements (like GUE or UTD) or allow instructors to add content (like NAUI or SDI and possible others). And for instructors for the latter, ones that do add content and provide a syllabus.
But just any ol' mainstream instructor? Save your money. Spend your money wisely. Watch out for "oh we'll fix it in the next class", and after you have a stack of cards and have spent thousands of dollars, you still have that issue needing to be fixed. That's one of the things I like about the GUE system (though I dive air, solo dive often, dive sidemount in open water, so their philosophy doesn't work for me in general). Just a few really solid courses. Requirements to have a minimum number of dives before the next course. Really meaningful courses that are expensive, and time consuming, but for the summed up cost of a bunch of courses from other agencies that equal the time and cost, you get a whole lot more typically (there are of course exceptions as there are some great mainstream agency instructors, but they are more the exception and not the rule).
Please remember that that the average instructor lasts a year and a half. How can that be when there are so many instructors that teach for a long time? Think gap year kids. Zero to hero. I don't blame the kids, as I can't think of a funner way of spending a year off before going back to reality/uni. How skilled of instructors can these kids possibly be?
Then you need to consider motivation. For many instructors that teach out of shops, they may get $25/student to get them through the confined water. They get another $25/student ONLY if the student gets certified. And I see students packed into these courses. I've seen an instructor teaching AOW to 8 students (the same guy who can't use a compass). How much learning can you get with 7 other students?
There's a reason why I don't take more than 2 students for recreational courses. I want them to learn.
Does my prior comment now make more sense?
