I recently got my OW and was surprised to read this. I was under the impression that serious divers naturally took the next level of training as soon as they could.
Why not?
There are two major schools of thought regarding AOW. One is that you should take it as soon after OW as possible, and the other is that you should wait and get some experience first. Which approach is preferable depends on what you want to get out of it and how your instructor wants to teach it. Both have advantages and drawbacks.
Let's look at the "soon after" approach first ... this is for people who are going after the experience of different diving environments. You're still struggling with the skills you were introduced to in OW ... probably your bouyancy control isn't very good, you have a tendency to "correct" your position using your arms, and you suck down a tank of air so fast the sides of the tank move when you inhale. So when your instructor sells you on the idea of a few more dives under his/her supervision, it makes a lot of sense to you, and you buy it. And it's true that you'll experience some different environments ... but a lot of people leave those classes feeling like they didn't learn anything, because the material that got covered ... if any ... was basically a review of OW. If they cover anything new at all it'll be in the areas of deep and night diving, and perhaps some navigation skills that may be a bit more than the simple reciprocal stuff you learned in OW.
Now let's look at the "wait and get some experience" approach ... this is for people who are trying to expand their knowledge as well as their experience. It's generally more difficult to find these classes ... because they're harder and more expensive to teach, and most instructors don't teach this way. The tipoff will be an instructor who encourages you to go out and do some easy dives, getting comfortable with your OW skills ... because that means they're anticipating that you'll need that "bandwidth" for focusing on new skills that will come with the class. These classes tend to dig a bit deeper into dive planning, more complex navigation, buoyancy control, trim and weighting, and perhaps other refinements. There may be some fun exercises, like a navigation "treasure hunt", learning to use lift bags and SMB's, and other types of skills that you'll find useful as an independent diver. In fact, the primary goal of this type of AOW class will be to train you to have the competence and confidence to dive comfortably without supervision. The major drawbacks are that you'll have to first find someone to dive with for a while, you'll have to put more effort into the class, and it will probably cost you a bit more.
Which approach works better for you depends on whether or not you learn best by doing (as opposed to being told what to do), how much confidence you have in your ability to dive unsupervised after OW, and whether or not "digging deeper" into core skills is important to you.
I know people who've loved and hated both approaches ... some who feel "cheated" with the former and some who feel that latter is overkill. It's really a personal decision.
... Bob (Grateful Diver)
