My instructor reasons that why proper weighting isn't really taught in the Open Water course, is so that they can concentrate on the other stuffs.
So, what they do is to have us put more weight than necessary, objective, so that we can descend.
Sorry if this post is a little bit late, but I just can't help replying to this one. Sadly, a large number of instructors do this. But good buoyancy is part of every OW course, and it's a skill that is taught from the beginning, and it's something you keep improving with every dive, regardless of how many dives you've had, be it 10, 20, 100, 1000. Proper weighting and weight configuration is a basic element of good buoyancy and good trim in the water. If you have friends who want to get into diving, tell them before they sign up with an instructor to talk to him, and ask questions about how he teaches his class, what he thinks is most important to impart to students, and so on.
I'm sorry for sounding a bit harsh, but the instructors who overweight their students and don't make adjustments while watching them move around in the water are just plain lazy and don't really care much for imparting good diving skills. Sounds like they are also the types to sell you Advanced certification immediately after your OW check-out.
With the right amount of weight, new students can go down and stay down, even for pool exercises. It's a matter of teaching and helping them fully vent their BCs, gain stability in their positions, like how they place their fins, etc. Sometimes, for people who can't find their balance, we do overweight them, but only during the shallow-water exercises, the ones you perform kneeling down in about 5ft of water. But once the swimming parts begin, we move them back to the correct weight.
Here's one sign that someone new may be overweighted at the hips (if you're diving in warm waters at least, and put all the weights around your waist). They dive with their head up, feet down, even if they're kinda froggy -- this is because they're thinking they're in a horizontal position. Because of this, with the movement of their fins, they tend to move upward, then they vent their BCs when they notice they're ascending thinking it's the air. They then sink, then add air; then they float up, deflate... you end up with a diver continually adjusting his/her BC, his/her hand always on the inflator hose. Some other people compensate by swirling their fins around, like a kitchen mixer, or by sculling. These people run out of air fast, and have trouble when there are currents.
From the illustration above, you can see that there are risks to setting free a licensed diver without proper weighting and good buoyancy.
(Of course, there may be a good few who are naturally instinctively good and don't experience this, but if you are overweighted, you'll notice that you do save on air once you are properly weighted, even if you're already quite efficient in your breathing.)
Sorry for the rant. Like I said, this type of line from some instructors is a pet peeve of mine.
But I'm very glad gnulab that you're taking the initiative to check on your weighting and asking how to do it right.
Dive safely and enjoy your dives!
