Okie,
I recently received an education on shooting release-triggers at the local trap range. I was looking to buy a decent used trap gun and was able to fire a few of the ones for sale by other members.
Firing a gun with a release trigger is a strange sensation (actually, pulling the trigger and holding it in prior to calling for the bird is the really strange part of it). About half of the time, I forgot to pull, called for the bird, pulled the trigger, nothing happened, quickly remembered, and then missed the bird as it passed its aped and was headed down.
As far as making the weapon safe once the trigger is pulled - - I was instructed to keep pressure on the trigger, bring the weapon down from my shoulder while keeping the barrels pointing down range, and "thumb" open the weapon without leaving pressure off the trigger until the weapon is fully opened.
I suppose that a very experienced shooter could make the transition with little effort. However, it seemed like more effort than it was worth for me.