I'd just like to point out the rules may say 'pulling' but in fact you will get hit with a penalty (sometimes a DQ) just for 'touching' the lane rope or wall before your airway breaks. A judge can't tell if you are pulling, or just swimming up but touching the wall. From my point of view it's a timing thing, touch or grab the wall a fraction too early and you will be done. I made this mistake last year in a comp, and it was so close the judges had to freeze the video and show it frame by frame. When my hand touched the top of the wall my airway was barely 2 cm below the water....
When I do max dynamics I pack close to 3 litres, and need a lot of neckweight 12pounds+ to compensate. In training I would breathe out before breaking the surface, then grab a hold of the wall to prevent going back down in the water. ie once I have breathed out, and not at packing volume I would sink. I know Tom S wears HEAPS of weight and packs a lot, so he has this even worse. A year or so ago he got a DQ (world record rules is DQ for this vs penalty) for this, he obviously needs to grab something to prevent from sinking. Grabbing the wall to support you at the end of a dynamic is by far the best option safety wise, for some freedivers is the only option. It makes it real tough you have to be %100 spot on with your timing and don't get any allowances for small mistakes.
Cheers,
Wal
