I\'ve heard this conundrum refered to as the \"Tank-Mage\" syndrome. Any game that enables a player to ultimately master everything, can\'t be one that supports RP. By definition, this game must support a \"Role\" for players which encompasses both their fighting and trade skills. The very word, role, implies plurality and diversification. Otherwise the game is simply a series of check-off boxes until you get them all filled...a monologue pursued by everyone.
A role must be developed by making choices and having options which are mutually exclusive of other choices and options. Merely creating a back-story for your character which is in no way tied to in-game mechanicsdoes not reinforce roleplaying.
This concept extends to quests. The more content there is that players simply can\'t solo and that require a mix of player talents to complete, the more players will be encouraged and valued for their diversity. Ideally skills like pick-lock ought to be acheivable via two seperate paths (a magic unlock in one school) so as not to force quest X to always require that a player on one, narrow path be included.
In another thread about weapon stats, there was some discussion about hidden numbers. I do believe hidden numbers provide some desirable mystery to the game while all-exposed numbers simply create an arms-race and a greedy marketplace. The controversy revolves around what these hidden numbers control and whether they are discoverable. In that other thread, a suggestion was made that sliders by used to alter how one used a weapon-for defense or attack and even to do different \"moves or stances-and that the performance of a particular weapon was tied to it\'s hidden number interaction with the players stats, probably Str, Agi & Sta although an enchanted weapon could certainly also be affected by the players mental stats as well.
While I don\'t like the idea of in-game, real time sliders to alter weapon usage, I do see where a set of preset hotkeys, each tied to an underlying, player adjustable matrix or graph, could be the basis for discovering whether a particular weapon was better suited to a particular player could be valuable. Additionally, once a player had a high enough skill in relation to the \"rank\" of a particular weapon, players could choose to divine, know, analyze or otherwise unlock the underlying numbers but only at the cost of making the weapon non-saleable to other players. A good player will have gained useful information from how a particular weapon performed against his presets and be better able to judge which weapons to keep and \"know\" in the future and which to sell.
While these weapon comments may seem a bit astray from this thread, I believe they back up the need for players not to have all the same stats and to be able to improve them, though not all of them on a single character. Someone posted in this thread that in real life you can\'t just go to a trainer and improve your strength. Of course that isn\'t true at all or where would all the gyms be today?
What one can\'t improve in real life, is their \"statistics\" beyond some absolute limit. This limit varies from person to person but, in the game these two numbers, your current ability and your potential ability, are not so directly tied....as yet. Effectively, your stat is the same as your potential. It\'s only the items you choose to use that may convert that potential in to greater effect or damage. Therefore, without a mechanism in-game to raise ones stats, the whole \"arms-race, higher-numbers\" mind-set is reinforced as it is the only way to \"get better\".
Ultima online had trainers where you could go to raise your weapon skills by repeatedly killing dummies. Other games simply increase your stats as you level. They do this largely to segregate players from items by quality or \"numbers\". In a more pure RP environment, a player ought to be able to have a very high quality weapon IF he\'s willing to put in the training time to be able to wield it and sustain the level of ability required to use it. Granted, this might make for a very narrow character but, with-in certain bounds, it ought to be an option available to a player if they are willing to sacrifice being better rounded. I see no reason why, upon acquiring by quest or hunt, some superior weapon that a player might not become consumed with the desire to master it...perhaps even compelled to in the case of an enchanted weapon.
As for crafting, I\'d have thought it was obvious that no one could possilby attain complete mastery of more that two skills in their lifetime. Ideally, the mastery of these two skills opens up the ability to craft very unique and valuable items by combining aspects of both skils sets. Of course, it\'s not truly obvious but in order for a game to maintain the value of as wide a possible number of crafers, at all levels, players ought not be able to master every trade skill.
Star Wars Galaxies had/has what at first glance looks like a good and complete crafting system. Unfortunately, it didn\'t turn out that way. Firstly, players were forced to craft through paths they had no interest in in order to reach ones they cared about. This had two effects, 1) the Market was flooded with cheap goods because they were being over produced and 2) raw materials became rare and expensive as too many players competed for them. SWG also had a system of quality attached to the underlying raw materials. In principal, this meant that players who sought out and figured out the best combination for making a particular pattern could make ones with superior stats....even for the lowest noob item. However the complete over abundance of every item due to over manufacture lowerd prices so much that the \"craftsman\" ideal was too expensive to pursue until higher levels.
Additionally, SWG failed to build in enough cross-dependancy between trade skills to create value for much of what a player was required or allowed to make in order to improve their skill. In a good economy, lower skilled players ought to be the source of components for higher skilled ones as well as being neccesary to provide components need in other skills. The argument against this was that turning off lower level items as a player raised his skill might create a \"bottleneck\" for higher players to advance. For me, it simply creates a valid reason to form a diversely skilled guild. If a bottleneck was to be avoided, it should have been relieved by making the same items available from NPC vendors but at higher prices than a player would need to charge for them. Soak the rich is always a viable game option !

To sum up this long post, there are positive options available to reinforce RP not just negative ones. Creating value in those roles and protecting it is the key. Unrestrained, \"free market\" captialism may or may not be an ideal economic system but it is in no way a useful tool for creating \"moral\" values. In the same way, a game that allows the creation of conglomerated, widely diversified player-characters may appeal to the power gamer but it does nothing to build community and encourage diversity which is the essence of RP.