PerroneFord:I'd spend 8 hours a week in the pool dialing things in. All too often I hear on this board about how bad the instructor is, or how bad the class is. You know what? Maybe so, but its YOUR butt there in the water. Work on it until you get it right. For some it comes quickly, for others it takes months. Not everyone learns at the same rate. Fact of life.
People choose not to educate themselves about instructors. They choose not to educate themselves about the environment they are about to enter. They choose a SCUBA class out of a magazine and are suprised when they have substandard skills. Want to learn buoyancy and skill down cold? Come take a week long O/W class from a good cave instructor. Class will be harder. You might have someone tell you the TRUTH about your diving. Suck it up and improve.
With the advent of the internet and sites like this, some people may enter OW knowing what they should learn. They know proper buoyancy control should be covered and they've also heard that it takes more than a weekend to learn it.
However, others may not know of sites like this prior to OW and they have no idea this is even an issue. They are going to go take a class that teaches them to dive. They have no idea how to pick an instructor and they have no idea how long it takes to become competent. The come out of the class not even knowing what competent means. They simply go down to the LDS closest to them and just sign up. At the OW level, the bulk of the blame rests with those responsible for the brevity of the classes, not the clueless student who has no idea what to expect from an OW class.