I would encourage you to take the course. I'm also happy you recognize this as an issue. IMHO, not until later in diving do divers see the benefits of mastering this.
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I would guess you'll learn more reading here than you will in a class on buoancy. It's a conceptual approach that you have to fine tune, like RichinNC said he did in a pool, based on your gear, body type and where you're diving.