The first dry suit dive I did I had the usual fun adventure of dealing with the moving air bubble in the suit. I quickly found myself suspended upside down, with all the air in my legs, feeling stupid and annoyed. For the second dive, I borrowed someone's ankle weights. It kept my feet down, the air up around my torso, and my position horizontal...problem solved. From my third dive on, I determined to achieve that same result without relying on ankle weights just by learing to control the bubble. It really isn't that hard. I think some people consider them a "crutch" because they allow you get away without really learning this bubble control. The main argument I've heard against them is that it decreases your efficiency. Obviously if every time you raise a foot to kick you also have to move an extra two pounds you will tire more quickly. It's the same reason why people add ankle/wrist weights when they run or walk, for a harder workout....and we all know scuba is NOT meant to be exercise in that sense.
