In my experience it takes more training to reliably take off a safety to fire and then re-engage after fire under stress then to simply keeping your damned finger off the trigger until the decision to fire.
But it's not about being proficient and effective, it's about being safe. If we can have a weapon with a safety AND keep your finger off the trigger, that's twice as safe! Plus we've saved money not having to shoot more in order to actually be proficient with the weapon.
Wink, next you're going to tell me we should expand base ranges so there can be more throughput, thereby allowing for more proficiency. I think we've had enough of your crazy talk.