Guys, I've played Dark Souls and finished it and I don't consider myself a particularly hardcore gamer. Honestly, I don't even think Dark Souls is that hard, it's a game that if you master your timing you can basically go through it at level 1 and beat every boss (eventually). Hell, to make an "easy mode", I wouldn't just reduce the amount of damage enemies do, I'd say you'd have to slow down their attack speeds and give the players more time to dodge or block. I don't really care about the prospect of an Easy Mode, but I'd say that anyone that hasn't played the game because they hear it's uber difficult should definitely try it to see what the fuss is about before they ask for one. Because the game's difficulty is not in the individual enemies or the amount of damage they do. The difficulty of the game comes from many, many factors, and the fact is that the majority of basic enemies you'll encounter between Bonfires aren't difficult to beat by any game's standards.
However, the OP's point is perfectly valid. Yes, it's easy to scoff at his examples, because the cliffs he points out will only claim your lives a few times if you're unlucky. But there are areas in the game where the difficulty is the environment. The Crystal Caves leaps to mind. You can get through to the boss fighting a bare handful of enemies (and of the foes you do fight, many don't even respawn), but I still died more times than I care to remember because of the invisible walkways. The Tomb of the Giants is sort of the same unless you picked up something that can light your way (by that point I'd nabbed one of those glowing larvae helmets and had zero problems with visibility), and there are a lot of regions like that. New Londo, for example, is full of ghosts that can only be hit when you're Cursed, can come out of the walls and ground and roof and hit you from any direction, and do all of this in areas where you're frequently on a narrow edge and easy to knock over. In Anor Londo, the bit where you charge the knight archers will kill you time and again without you ever taking a single spot of damage, because they can just knock you off the ledge. Sen's Fortress does the same with many of its traps. The list goes on.
The thing I think the OP is getting at is that an "Easy mode" for Dark Souls would require an enormous overhaul of every design aspect of the game. Otherwise, the easy mode turns the game into a very harsh environment populated by gimped monsters. And for a game that, frankly, if I beat most people interested in the title should be able to beat without much trouble, that doesn't sound too attractive.