About the arguments being repeated, the thread itself is an iteration of many other ones asking the same thing...

But then, now is an interesting time to revisit it, as Nerekhall is out and has the influence mechanic that addresses some of these issues. You could probably house rule some retrofitting using these mechanics for older quests too.

In the given example, maybe there's a choice between Frederick attacking the players, or the Overlord getting to re-inforce an extra monster group or bring a different lieutenant in. It would still favour the Overlord of course, unless you did it random/blind like some of the Nerekhall quests.

This topic seems to generate disproportionate levels of passion in discussion, in my experience.

RAW says all players can read the quest guide whenever they want, so nothing is truly hidden. If something is meant to be obfuscated (like the exact location of the unique search token) then the quest rules will be written in such a way as to randomize its location. Reading the quest guide will never reveal anything that shouldn't be known.

That said, some players like the RPG atmosphere and so choose to hide differing levels of info to suit their tastes. As long as everyone at the table is happy, I don't see a problem with that.

I also don't think that the heroes are obligated to read the quest guide, either. They're allowed to, sure. It's probably a wise idea. But if they choose not to, I don't see why that's a problem. As long as they're aware of the option, choosing to decline it is their choice to make.

BTW the OL could also choose not to read the quest guide, so that he is "surprised" when the heroes pull out a win.

While hiding info gives fun surprises for the heroes, there is a very good reason I suggest letting quests be public:

Because when I'm the Overlord, I can't remember everything on the quest, or read or interpret it wrong. I give the book to the heroes and tel lthem to read it in their downtime to find objections or contradictions to what I interpretted.

This helped a LOT of quests from being done wrong.