Why would you want to ruin the surprise and sense of adventure for a first-timer? Some like MMOs for the very sense of discovery and the large extent of those that they can provide in comparison to other games. Dying, wiping, having to try again is all okay. People learn from their mistakes and most often gladly listen to the tips during a dungeon. It'll just take a while longer to reach the end if KOs occur. Expecting a first-timer to powergame is just plain virulent.