As a DM, I don't want my players to see what the roll was, I prefer to tell them (if I decide to use it). So for example, if they do a crit and the roll ends up being "actually, not a crit", I wouldn't want to use it, so I would just not tell them. Same with loot, I'd only let them know what the loot is if they search the body, etc.. Having all the rolls happen as whispers only would be a requirement for me.
As a DM, I don't want my players to see what the roll was, I prefer to tell them (if I decide to use it). So for example, if they do a crit and the roll ends up being "actually, not a crit", I wouldn't want to use it, so I would just not tell them. Same with loot, I'd only let them know what the loot is if they search the body, etc.. Having all the rolls happen as whispers only would be a requirement for me.