I never done it in an RPG, but my first LARP used Save-Points, but it was a very special scenario
It was classic Fantasy but we died in the first scene, then we were picked up by the Death-God who said that the Underworld has some problems and if we fix them then we will be returned to life. Our main problem was time since we only had till Dawn (the game played from Dusk till Dawn) to do it.
Since we were already dead he offered us a limited number of "Saves" where we could reset to, our Items and Lifepoints would also reset to this point but we would keep our memories so we could work out new strategies. The thing was that the scenarios were very hard and the time was quite short (we didn't make it to the end) and we even had to save after players died (=permanent death, I was the first victim

) since we couldn't afford to do the scenario again. Also we had less saves than scenarios so we would sometimes really lose MUCH time to reset.
So it was very fun and shows that Saves can work, at least in such unusual scenarios,...
