Without Rule Zero, a DM's campaign becomes susceptible to change at the whim of the designers of 4E. What if (for example) a DM doesn't have tieflings (or even demons, for that matter) in his campaign world? Must the poor DM either wedge into his campaign tieflings and all the other things that do not fit into his campaign world, or else scrap his whole world altogether and start a new one that incorporates all the stuff in the core 4E books?
That would be preposterous. A DM can spend countless hours over the course of years lovingly crafting his world. Conversely, a player character takes a number of minutes to create. To insist that the DM with his campaign world (representing years of work) compromise it on the whim of a player who spent 20 minutes min-maxing his new character is absurd. It would be especially egregious for a new player to join an established group and (by insisting upon some sort of character provided for in the 4E Players Handbook) try to change both the parameters of the campaign world and the feel of the group. Suppose (for example) there were a group of D&Ders who had been playing a "3rd edition rules, 1st edition feel" campaign (similar to that presented in Necromancer's products) since the advent of 3E. Then suppose the group converted to 4E, keeping the same campaign world. Finally, suppose a new player wanted to join but insisted upon playing a tiefling, regardless of any consideration besides the fact that tieflings are described in the 4E Players Handbook. It would be simplest to simply nip that in the bud by having a DM's clause such as I described in the opening post of this thread.
That would be preposterous. A DM can spend countless hours over the course of years lovingly crafting his world. Conversely, a player character takes a number of minutes to create. To insist that the DM with his campaign world (representing years of work) compromise it on the whim of a player who spent 20 minutes min-maxing his new character is absurd. It would be especially egregious for a new player to join an established group and (by insisting upon some sort of character provided for in the 4E Players Handbook) try to change both the parameters of the campaign world and the feel of the group. Suppose (for example) there were a group of D&Ders who had been playing a "3rd edition rules, 1st edition feel" campaign (similar to that presented in Necromancer's products) since the advent of 3E. Then suppose the group converted to 4E, keeping the same campaign world. Finally, suppose a new player wanted to join but insisted upon playing a tiefling, regardless of any consideration besides the fact that tieflings are described in the 4E Players Handbook. It would be simplest to simply nip that in the bud by having a DM's clause such as I described in the opening post of this thread.