One of the implicit design goals of 4E seems to be to reduce the influence the DM has over the game, particularly as it relates to "fun". Now, I say "implicit" because this goal is wholly unatainable so long as there is a DM at all. Even so, there are some design decisions that can be made -- and appear to have been made -- that can attempt to ensure a more standardized experience -- a certain quality and minimum quantity of fun, if you will -- for the players.
Some of the elements that I think contribute to this implicit goal (in no particular order):
Level/Tier Based Encounter Design: The successor to the CR system, this system seems to be designed to ensure parity or balance between the PCs and their opposition even more rigidly than the CR system with the inclusion of tiered monsters. moreover, monster/encounter design has gotten a lot of attention, it seems, all with an eye toward balance.
Quests: While "Quest Cards" may be optioonal, it seems that Quests themselves are an inherent part of the rules for adventure design. What this does is clearly lay out the goals and rewards for achieving those goals at the beginning of play, thereby limiting or even eliminating DM interpretation of the players' performance as a matter of what rewards are gained.
Roles: PC roles, particularly in the sense of "minimum competency" in the role's specific field, in or out of combat, means that a party composed of the proper roles will always have the tools necessary to overcome a challenge. that is to say, if the DM also uses roles for monsters and other kinds of challenges, as has been suggested, the PCs are by default always equipped to meet the challenges head on (whatever that may mean for a particular challenge).
Magic Rings: This is a specific example of a general attitude toward codifying certain aspects of the game that were once open to DM interpretation and decision making. While all editions of the game have lobbied the DM to avoid giving PCs inordinately powerful and/or numerous items, and 3E went so far as to create quantified guidelines as to what this meant, 4E is the first edition to actively prohibit lower level PCs from using "inappropriate" iems (in this case, rings). The players, therefore, have been spared from the DM's ability to ruin the game by loading them down with too much stuff.
In general, the more codified a set of rules is and the more specific the guidelines for a greater number of aspects of play, the fewer aspects remain in the hands of the DM. of course, theoretically a DM can houserule/ignore/exclude anything her or she likes, but I think it is far more common for the DM to generally follow the rules and "fill in the gaps" with Fiat. With fewer gaps, there's then less Fiat.
Whether this is a good thing or a bad thing is deopendent entirely on playstyle, preference and expectations. I consider it a bad thing -- I think the game should give the DM both more powers and more responsibilites, going "backwards" away from 3E's highly structured ruleset toward earlier editions' more open rulesset. And while I do understand that bad DMs exist that use Fiat and vague rules to shine their viking hats, the answer to these DMs is simple: no players.
Some of the elements that I think contribute to this implicit goal (in no particular order):
Level/Tier Based Encounter Design: The successor to the CR system, this system seems to be designed to ensure parity or balance between the PCs and their opposition even more rigidly than the CR system with the inclusion of tiered monsters. moreover, monster/encounter design has gotten a lot of attention, it seems, all with an eye toward balance.
Quests: While "Quest Cards" may be optioonal, it seems that Quests themselves are an inherent part of the rules for adventure design. What this does is clearly lay out the goals and rewards for achieving those goals at the beginning of play, thereby limiting or even eliminating DM interpretation of the players' performance as a matter of what rewards are gained.
Roles: PC roles, particularly in the sense of "minimum competency" in the role's specific field, in or out of combat, means that a party composed of the proper roles will always have the tools necessary to overcome a challenge. that is to say, if the DM also uses roles for monsters and other kinds of challenges, as has been suggested, the PCs are by default always equipped to meet the challenges head on (whatever that may mean for a particular challenge).
Magic Rings: This is a specific example of a general attitude toward codifying certain aspects of the game that were once open to DM interpretation and decision making. While all editions of the game have lobbied the DM to avoid giving PCs inordinately powerful and/or numerous items, and 3E went so far as to create quantified guidelines as to what this meant, 4E is the first edition to actively prohibit lower level PCs from using "inappropriate" iems (in this case, rings). The players, therefore, have been spared from the DM's ability to ruin the game by loading them down with too much stuff.
In general, the more codified a set of rules is and the more specific the guidelines for a greater number of aspects of play, the fewer aspects remain in the hands of the DM. of course, theoretically a DM can houserule/ignore/exclude anything her or she likes, but I think it is far more common for the DM to generally follow the rules and "fill in the gaps" with Fiat. With fewer gaps, there's then less Fiat.
Whether this is a good thing or a bad thing is deopendent entirely on playstyle, preference and expectations. I consider it a bad thing -- I think the game should give the DM both more powers and more responsibilites, going "backwards" away from 3E's highly structured ruleset toward earlier editions' more open rulesset. And while I do understand that bad DMs exist that use Fiat and vague rules to shine their viking hats, the answer to these DMs is simple: no players.