At the gym I go to, they use GriGri's exclusively, but they teach belaying as if it was an ATC. So, never let go of the rope, always be ready to lock it off, if you let go your partner will hit the deck, and so on.
This seems like the best of both worlds. You can evaluate a belayer across the other side of the room, by making sure that they are managing the rope as if they were using an ATC. But there's an extra margin of safety for when they get lazy, or briefly forget what to do. |