My mileage does, extensively. I'll tentatively agree that what most consider "ad-libbed" may feel shallow, but this is largely due to the fact that it occurs in game systems that don't have tools to support it very well. D&D is one such. Still, my Sigil campaign had large sections discovered in play, and it had a great deal of depth to it.
I think the game itself though is a different type of game. I'm pretty open to trying things but again a D&D campaign for me is a commitment of time and energy and I want the biggest bang for my buck so I tend to favor what I like a lot in those situations.
Of course the GM has to ad-lib some things, but if you're preference is to minimize this, you should really ask what that achieves in play -- how does it support what you want. The "depth" argument is weak -- this is often trotted out but it's not every strongly presented.
@Lanefan has done the best job I've seen, and what that boils down to is a GM's desire to plant lots of extra details to essentially chaff player skilled play -- it's an additional layer of challenge to skilled play.
Well by minimizing ad libbing, it means the world pre-exists the PCs. It is a living breathing world.
I think a way to think of it is a book analogy...which would you prefer an author who just off the cuff tells a story that he makes up from scratch or would you prefer an author who spends time crafting the story which you then consume as a book. Now I'm not saying it would be impossible for me to enjoy an off the cuff story made up from scratch but the odds astronomically improve that the well crafted book will be better.
So again, when I've played in games where the DM makes it up as he goes I've left the session, my last one by the way, feeling code and not like I had much fun. Obviously, if the ad libber could fool me utterly then it wouldn't matter but I don't see myself being fooled too many times. Definitely not across an entire campaign.
I wasn't painting your playstyle as anything. If anything I was pointing to how preferring a GM heavy prep in a sandbox world offsets the opportunity for Force. Force isn't a negative thing, in my opinion, but rather something that's a tool in the box -- it can be abused like any other. Heck, if you're dealing with encounters keyed to the players, that's using Force -- the GM is using their authority to generate a preferred outcome regardless of the player choices, in this case a balanced encounter.
And disagree -- I think this is actually impossible, and what's considered this is more a specified approach as to how you're expected to do this. Like pretending that your character doesn't know fire hurts trolls -- when is it okay to stop pretending you don't know this? I mean, your actions are already impacted by doing so -- there's never going to be that spontaneous "I hit it with a torch" that a newbie could do, because it'll be labeled, so play is already distorted. I think that persisting in believing you can actually separate these things prevents understanding what it is you actually do want out of play and doing things to get that.
Well now you've digressed into player characters. I've given up fighting the player knowledge battle by trying to keep the books from them. I just rename and change up a lot of things so that it remains new each campaign. They may figure out something is a troll eventually but again perhaps trolls are somewhat in the collective knowledge of society. Dragons breathing is definitely something that most peasants know not because they've seen a dragon but have heard the legends.
When I play the monsters, I have a reason for their existence and I have their motives and plans mapped out. I then go through some scenarios. I ask questions. For example, if the orc chieftain hears swords clashing in the next room what does he do? If I say he charges into battle, I don't change that up when the players deliberately set a trap for him and clang their swords. I try to assess the monsters intelligence and other factors like instincts, cleverness, craftiness, etc... Those things decide how I devise their response plans.
There may come times when I have to make a decision. Sometimes I dice for that decision based on probabilities. I try to avoid just choosing the obvious course given DM knowledge versus monster knowledge.
I do enjoy our conversations and the fact that we can debate this issues civilly.