A good instructor will work at the edges a bit until s/he sees how you learn best. THEN, the instructor will work through some formulas based on how you understand things. And if you regularly think in feet instead of meters, then your class will be i feet, not meters.citykid:Lemme ask a question here. I am getting ready to take the NAUI nitrox course... it gives me ten different ways to figure out something... am I going to have to know every single way (mathamatically) to come to an answer, in feet AND meters?
Most good instructors want you to be able to problem solve when there's no instructor around. That means the instructor has to find a reliable way for you to use the stuff you learn. Some stress formulas, others stress concepts. After a good class, you'll walk away thinking you already knew it!
If you get the class that takes you to a 25' quarry for a nitrox dive, call a foul, then call NAUI!