This is what I think
@Charlaquin and
@iserith have been getting at, and why the whole thing about using dice to resolve uncertainty point is so important, and not pedantic/semantic. Since players control their characters' action declarations, there's no uncertainty, and thus no roll is needed.
(One might argue that "being intimidated" isn't an action declaration, but, as I pointed out, if being intimidated doesn't restrict action declarations then it's just a roleplaying cue, and if it's just a roleplaying cue does it really need mechanical reinforcement? That smells to me like not trusting other players to roleplay.)
Interestingly, the opposition to their stance seems to fall into two camps with similar but opposite arguments:
@Lanefan seems to agree that there's no uncertainty if the PC's player claims there's no uncertainty, but that the same is true of NPCs, with the DM being the "player". (And I sort of agree with him: it is up to the DM to decide if there's uncertainty in those cases.)
The other camp says that there
is uncertainty, that just like players can't declare their weapon hits, they can't declare they aren't intimidated.