gamasutra
Obsidian's J.E. Sawyer talk at GDC Europe, I selected parts of it here, great read, a lot more on the site.
Obsidian's J.E. Sawyer talk at GDC Europe, I selected parts of it here, great read, a lot more on the site.
Gamasutra said:Five Hard Lessons
1.) Mechanical chaos -- "randomization as a means to resolve a gameplay conflict" -- is "very frustrating to players," said Sawyer.
Contemporary games which offer FPS-like interfaces still rely on randomized accuracy, which drives players nuts. His own company's Alpha Protocol is one example of this. "No actual human being likes this! You really struggle to get to the point of competence in the game," said Sawyer.
When it comes to randomized lockpicking/hacking/speech/crafting etc., "All it causes is this: 'Yay! I'm gonna reload the game!' There's nothing to prevent me from reloading. Any of these checks where there's something important on the line... It just results in degenerate gameplay behavior."
In short, with this sort of gameplay, gamers have bad experiences "not because they did anything wrong, but the game capriciously decided you fail."
Mass Effect changed its combat from 1 to 2: "Most of the weapons feel a lot better, and what they did was make it feel like a more traditional shooter in many ways," said Sawyer. 

2.) What you perceive in a game is ultimately what matters the most -- Mass Effect had tons of weapons but they were barely differentiated. They had incremental stat differences only.
"What's the chance that a 5 percent difference is going to make you take the enemy down in one fewer hit? If it takes me four shots, but the fourth shot killed him a little more, that doesn't mean anything to me," Sawyer said.
In Alpha Protocol, "The player could get abilities to upgrade their stealth but often they couldn't see the effects in the game," he said. It was widely considered to have a broken stealth system. "It was a cool idea but certain aspects of it didn't feel good because it didn't feedback to the player."
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3.) Strategic failures feel really bad -- In an extreme example, he mentioned that The Bard's Tale, a 1980s classic, required you to have a bard in your party to progress past a certain point -- something that was not telegraphed by anything but the game's title.
More relevantly, Icewind Dale and Temple of Elemental Evil required the player to create entire parties at the adventure's outset. "The games were tuned for D&D veterans. There are tons of ways you can make strategic errors. There are tons of ways you can make bad parties. What happens is 20 to 30 hours into the game, you can't go any further."
"Yes, the player made the error but we placed a high demand on them," Sawyer said.
In Fallout 1 and 3, specializing in "big guns" was not that useful, as there were few such weapons and they didn't show up early in the game -- neither of which the player could know at the point of character creation. "In Fallout New Vegas, we got rid of the big guns skill and pushed those guns into other gun categories."
"We kept the idea, we wanted the experience, but we didn't want them to have to deal with the weird system," he said.
"I don't see a compelling reason to not" let players re-spec characters that aren't suited to the gameplay design in an RPG, he also added.
4.) Player vs character is a false dichotomy -- "In every game you are expected as a player to use the resources available to you. A player very consciously makes decisions on how to build their character, so really it's about what do you ask the player to do over the course of a game," he said. "You have to be cognizant of what you're demanding of people."
Some games expect the player to manage too many options at once, and often developers argue that this is "dumbing down" the game to reduce them. However, he said, "This isn't about whether an RPG gamer can play twitch gameplay, it's about if a player is asked to manage a lot of stuff you shouldn't ask them to."
"Mental awareness and their ability to engage what's in the game," is something developers need to better pay attention to, said Sawyer.
5.) Summing up the importance of strong gameplay,
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Never create gameplay mechanics simply because that's "just the way that RPGs are," he cautioned. "If we ignore the lessons that those games [in other genres] teach us then we're really limiting our audience's ability to have fun," he concluded.
Syraxith said:this is a slide from his presentation, more here.