All I can say is, I am glad there appear to be GMs for all player styles. Many of us play very different styles of game and would find ourselves mutually incompatible. I’ll share my extremely long-winded thoughts on a few issues.
- Powergaming/Min-Maxing
I confess: I am a shameless optimizer. I start with an image of a character in my head and a superficial idea of his capabilities. Then I am build him in a way that is utterly devastating. I will take one level dips in prestige classes, I will create synergies, and I will do all sorts of reasonably original things well within the constraints of the rules from books all over the map. This isn’t subordinating role-playing to roll-playing: this is taking an idea I have and turning it into something awesome. My last swordsage/ardent was practically a work of art, if I do say so myself, and a very simple build.
Frankly, I enjoy doing this. I do not do it to punish DMs. I don’t do it because I am a munchkin with no control over my real life. I do it because optimizing within constraints is enjoyable to me for its own sake. Shockingly enough, I do it professionally as well.
I do the same thing as a GM. I expect my players are going to optimize and create suitable challenges. This isn’t a contest to see who has bigger balls: I want the players to feel rewarded for overcoming difficult problems with clever ideas on the spot and well-designed characters. I try to err on the side of too challenging, knowing that it is easier to tone down or remove encounters on the fly than it is to ramp them up. And absolutely none of this compromises flavor, character, or atmosphere.
My current character is a very simple Beguiler with a one level dip in Mindbender. Between feats, gear, and spell choices, he is just splendid at crowd control and locking down foes great and small. My GM has accepted the fact that it is rare for ordinary monsters to make their Will saves. It does happen, though, and I certainly do not bitch about it. 
Rather than try to limit my character, she just makes his lockdown skills a requirement for us to win battles. If I don’t charm/dominate/fascinate/entangle/etc enemies successfully, then our party will wipe. Same goes for the other characters in the group.
Again, as a GM, I accept that I am playing with clever players with well-built characters. Sometimes I plan an intricate encounters with twists, turns, and drama. And sometimes my players are going to utterly disembowel me from the beginning of the fight, crushing my great ideas under boots of striding & springing. I just have to let it go and shelve the unused twists & turns and save them for later. Alternatively, sometimes I end up inadvertently bruising my players with an encounter I thought was throwaway. These are great times to bring those twists back out of retirement.
I try to be flexible, let my players do what I want as long as I am having fun, and try not to be too attached to my creations. I am not the director of the show.
- Forensic Play
I definitely discourage this both in-game and out of game. As above, gaming is not a contest between me and my players. If they want or need something, I see it as my responsibility to find interesting ways to give it to them.
I have been in games where GMs tried to reign in the wealth and capabilities with an iron fist. As a consequence, we as players took everything that wasn’t nailed down. We just instinctively resisted the control and the entire exercise became more competitive: how can we extract wealth within the rules despite the inclinations of our GM. Fortunately our GM realized this, we all had a talk, and we all readjusted our expectations and style. Life for everyone improved.
Like Manda Jo, we absolutely love good gold sinks. We trick out our boats, bars, and brothels to the nines. Not only do these dispose of resouces, they also make fantastic adventure fodder.
- Realism
I find this irritating more than anything. It is a game. The rules are abstractions. We use the rules because they are practically useful. they may not be perfectly descriptive or work under all conceivable circumstances, but they are internally consistent and intuitive.
As a wizard, I simply expect to be able to target a spell anywhere line of sight and line of effect permit. The possibility of me mistargeting is baked either into the saving through or the touch attack. End of story. If this is too much for a GM, to handle, I would ask him why he does not make the fighters roll to see if they can successfully lift their weapons before they actually roll to hit. I do not play in games characterized by this sort of thing, though I know plenty of people out there love it. It takes all kinds.
If a player has a “realism” issue, I give him about 30 seconds to make his case. Then I make a ruling. Sometimes players are right, and I am happy to throw in positive or negative circumstance bonuses, especially if the player has a really good idea. But frequent arguing over issues that are not material is a great way to get asked not to come back.
My players and I have a sacred and very simple contract. Everyone wants to have fun, and everyone is going to contribute to an environment where we all can have fun. My players know that I will do whatever I can to give them what they ultimately want to get out of their experience. All they have to do is trust me. I ask them to trust me, to exercise a certain amount of self-restraint, and to respect the direction I am trying go with the game. We speak about these things openly and honestly when they come up.
