I'll admit, like others have done on both sides of the argument, the discussion regarding the word
solve is not an interesting one.
When I provide the PCs a riddle, I can ask them to solve it.
When I provide a word, I do not ask them to solve it, I ask them to create/establish the riddle that would prove the word to be the answer.
The more interesting part of the discussion, and I'm sure it has been either wholly or partly answered in this entire diatribe, is how games that play with story-now handle mystery adventures.
(1) Are they set as a Skill Challenges with x checks meaning the GM needs to have wrapped it up in X rolls? Or do they follow the narrative organically without a preset limitation?
(2) How do the negotiations between player and GM occur?
For instance, PCs discover a dead body, I imagine players declare they do a search of the body/area - group Investigation check called for.
(2a) Success is attainted. Does the GM narrate what is found or does the table?
(2b) Failure is attained, severity of the failure is determined by the dice and it is a GM move right? soft or hard.
Could the soft move be - you find the murder weapon thrown in the gutter. It is the (randomised) PC's dagger, which had been considered
misplaced some days ago.
Could the hard move be - the town guard turn up with a senior town official who announces they are taking over the investigation and the PCs are ushered out of the area.
(3) Or are both those considered hard? How does one differentiate between what is a hard move or a soft move by the GM?
EDIT: The reason I ask all this is because I'd be curious to try this out in our D&D game. We've done plenty traditional mystery-quests and I will keep doing these, because the players enjoy overcoming obstacles,
beating the DM, solving the mystery - but I could easily insert this style of mystery-adventure and have fun with this at the table too as we attempt to establish a narrative from a randomised scene frame.
I'm thinking each player at the table comes up with starting mystery and we let the dice determine which one we try establish through play.
And following
@Manbearcat's advice upthread, the mechanics to be used in establishing the mystery will all be overtly communicated/signaled to the players upfront as we engage with this new style of play (to us at least).