But then, in this or the other thread Ahn, you stated that your players don't play core casters, don't use item creation feats, don't buy magic items and don't have significant down time.
...
So, at least in your games, I can totally see why you don't have major problems. The problematic classes aren't present and your playstyle discourages the rest.
I never said they don't play core casters; wizards are a bit uncommon but I've had quite a few druids (generally considered the most powerful class) and some clerics and sorcerers as well. And yet no CODzillas.
Add in the fact that you tend to use one or two big encounters, rather than a large number of smaller encounters and you're pretty much playing right into the dead center of sweet spot for 3e.
That's a bit more interesting.
First off, the leveling guidelines make it nonsensical for people to face multiple encounters quickly (at one battle a
month even a half-orc passes level 20 before reaching retirement age). In world considerations also make this nonsensical in most cases.
Second, the by the book definition of a challenging encounter (four characters against one of equal level) is not very challenging; the book estimates that it should only use 20% of your replenishable resources and even that seems rather excessive. In other words, facing multiple encounters in a day isn't that different than facing one unless you really push the number or the difficulty.
Third, playing a smaller number of stronger encounters (what I do) is a playstyle that actually inherently favors spellcasters because they don't generally have to worry about conserving spells (though it devalues healing).
So when people talk about facing repeated encounters challenging enough to place strain on their available daily spells, I'd say that's pretty atypical and also should be pushing the spellcasters and such, not making them more effective.
However, when you start talking about how widespread this is, I really think you're looking at things simply from the bias of your own game.
I (as everyone) am pretty oriented around my own game. However, when you start talking about how widespread 3.X era spellcasters and other characters are
right now (4 years after the 4e release), I think I'm speaking for people other than myself as well. You don't hear those complaints from the PF player base despite its size and diversity and the fact that the rules do very little to address them. A significant number actually tried 4e's "fixes" and went back to the 3e mentality. Why do you think that is? Do they enjoy having casters dominate their games? Do they enforce their own fixes? Or do they simply not have any dealbreaker level problems with the basic play experience that system provides?
Think about it this way. If I sat at your table, played a conjurer wizard with item creation feats, I'd wreck your game. It's plain and simple. I'm not taking any unbalanced stuff, core only, and I'm not deliberately trying to break anything. But, simply through the options that are available to me, I'm going to do very bad things to your game.
No, you wouldn't.
No one has yet, even using some very unbalanced non-core rules, despite my starting from scratch as a DM and running a variety of different types of game with dozens of wildly different players over the years. I'm not sure why you think your impact would be so unintentionally disruptive.
I do think that it would be a very informative experience for some of the players who talk about 3e as if the whole game was "unbalanced" or who use some of the general edition warring criticisms (healbot, 15 MAD, linear/quadratic, etc.) to play in one of my games, or to play in other games in general. Unfortunately, I'm not available to run anything more than I already do.
Now, is that my fault or the system's fault? Me? I blame the system. The system should not be so fragile that choosing default options (conjurer wizard with bonus feats taking item creation feats is hardly outside of default) breaks the game.
Well it shouldn't. And it doesn't.
So, no, I do not have the same experience as you. 3e is most certainly not the best balanced system IME. AIR, you haven't actually played earlier editions have you?
Is 3e the best balanced system ever created? No. It's good enough though. I do consider it the best balanced version of D&D (followed by 2e, and would probably be followed by the early iterations of D&D if I had any knowledge of them).
I did play 2e for a couple of years before 3e came out; the earlier versions of D&D that one hears about on these boards are well before my time. We had the same conversation about switching from 2e to 3e that we had about switching from 3e to 4e (albeit with a different outcome). We did dungeon crawls and even one published adventure. I have some very anachronistic experiences. Good times though.
I find 2e to be outdated, confusing, and somewhat unbalanced, but an entirely enjoyable and viable game that I would be happy to run. IME 3e is a very natural evolution of 2e that addresses most of its problems, while still being well short of perfect (and I would welcome a new rpg that addressed 3e's problems in the same way; it's certainly time).