For the delicate work breasting out the bulk of the meat my index finger is along the spine, finger forward like a scalpel. This gives me lots of control to not perforate things. The breasts require slicing carefully between layers of meat and ribcage. It's awkward work because the bird wants to roll around. This knife is outstanding in this grip.
At joints, it's more of a ham-fisted, hammer grip. Separating the joints involves both cutting and lateral prying, heavy tendons against bone. The handle can be slick at this point so the handle shape is important to still provide a sure grip.
My hands were cold and stiff, with almost numb fingers (it was snowing and damp). Grip was never compromised.
I had the most trouble unlocking the lock after the job was done. Cold fingers and some lockstick didn't help. I actually had to find a stick to pry the lockbar back.
But I selected this knife specifically for the tough steel and the handle I had confidence using in cold, wet conditions.