Ovinomancer
No flips for you!
It's interesting to me that a hard decision for a player is being referred to as "not a challenge". To me that's the greatest kind of challenge in an RPG. That said, I'm going to avoid defining challenge and simply look at various situations whether they be challenges or not and how they effect play.
Consider a persuasion attempt on a PC. Whether there is risk or not will depend on the thing the PC is being persuaded to do. So for this example, let's assume there is a risk to being persuaded. That would mean we could define success as not being persuaded and remaining in the status quo and failure as being persuaded.
So then what happens when that persuasion is resolved mechanically
-The player sits out of the loop and has no input on how their character would react (which also means they have no conflict of interest in how their character is reacting)
What if the persuasion is resolved by player decision based on the actual argument provided and any other aids (such as an NPC persuasion roll to indicate how well orated the argument was)
-The player is solely responsible for choosing whether their PC succeeds or fails, which runs the risk of a player making the determination for out of character reasons, but when the player avoids out of character motivations and attempts to reach the decision to pass or fail, they are facing nearly the same mental challenge that their PC in the game is facing.
I can see where for some the style I'm advocating for would be impossible. Some would always rely on out of character motivations if given the opportunity. But for those that can avoid that, I cannot see how the style I advocate for isn't far superior.
You're imagining bad play, and so it is bad. Go back to the example I presented about the knight and the maiden. All the results of that were from the knight attempting to do things -- ie, player initiated. All of the outcomes were due to what the player explicitly had up as stakes -- ie, player initiated. These are in game where the GM's authority is much more limited and the players have greater authorities -- but they tend to move the boundaries around. If you're imagining D&D where the GM gets to declare player actions as well as having the authority over everything else, then, yes, this is a problem and should be avoided -- we agree wholeheartedly.
But, outside of that kind of D&D framework, things work. Hence the reason I keep bringing up the D&D framework and people not looking outside of it as being an impediment to understanding.
But, to go back to choice not being a challenge -- you can't lose a choice. You've not staked anything prior to the choice (at least in the examples given). You're just choosing between options. And, as I noted above, there's a heavy sense of these options being GM imposed anyway. I mean, your chastity or Excalibur example -- who set those stakes? Did the player decide that they'd risk their chastity to get the sword or was it, as presented, the GM saying that you can have the sword if your break your chastity? If it's anything at all like the latter, isn't this just the GM using force to set stakes for you?