There have been a lot of discussions, debates and arguments about dice rolling over the years. Perhaps the biggest is rather or not for a GM to hide his dice rolls from the players.
Well just for fun here is my two cents on the subject.
As a GM I have to say I favor hiding my rolls from the players. After all, this is why they invented the GM screen after all. I mean why make an item to hide what the Gm is doing if your not going to hide what the GM is doing. Yes the charts and information on the screen is useful, but you could have the same information on a sheet of paper without having a piece of cardboard in front of the GM.
Another reason to hide the rolls is so a GM can fudge them from time to time. Now as a GM I do fudge my rolls and will admit to it. However, the only time I fudge them in my favor is why my NPCs can’t seem to hit the barn they are standing on top of. I mean seriously, if the characters aren’t getting hit once in awhile where is the threat?
The main time I fudge them is in favor of the characters. While I have killed a character of twelve in my time as a GM, I don’t try to do so. If characters keep dying players loose interest. So, I fudge rolls when I know for sure the character is dead if I don’t. This is not to say I won’t kill a character, just try and help them.
I mean if I roll a critical hit on a badly wounded character; I’ll make it a normal hit instead. If I roll maximum or almost maximum damage on a character I will reduce the damage. I do little things like that to help the characters out.
Now if I hit the character again I may not worry about saving the, I mean yes I will help you but you have to help your self too. These are the fudges I will do and why I like to hide my rolls.
Another disagreement is should the GM make rolls for the characters. For the most part I say no, let the players roll for their characters. However there are some instances where it is better for the Gm to make the roll.
Luck; a character doesn’t know when his luck roll is made only when something lucky happens. Now of course them seeing the roll have little affect but it is “funnier” as a surprise.
A miss roll on the other hand can influence thieves. If a thief fails their find trap roll they will usually want to recheck. I will sometimes make the find trap rolls for a thief. The answer from the Gm is always the same regardless of the roll “You don’t find a trap” now the player can decide to check again or not. Of course the question the becomes “do you always check twice for traps”
So I think that they answer to both question is yes. GM should hide their rolls and they can and maybe even should make rolls for the players from time to time depending on the situation.
Just my two cents.