Since a flashback can't change what's been revealed so far (you can't go back and kill the person you're talking to), does that make flashbacks harder to do* because you greatly limit what kinds of failure are possible? (The character obviously didn't get detained for half a day or beaten or maybe even get recognized). Would a failure be something like something caused the target to notice the gun had been messed with, for example?
* Edit: I mean, "make them harder to run than the things happening in the present"
It's an interesting question and I bet you'd get different answers depending on who you ask.
I think that navigating Flashback scenes in BitD can be a bit tricky because you don't want to introduce any kind of contradictory information or logical inconsistencies. So, I think they require more care than scenes in which a GM is free to narrate or introduce information however they like.
But I think the constraints actually help in that they narrow the range of possibilities. In most cases, it's pretty easy to avoid contradictions, and those barriers help to focus on available avenues. So to lean on your example, we know we can't kill the guy who's in the "present" scene with us... but that gun he laid on the table? Maybe there's something we can do with that.
As I read @hawkeyefan's post, it wasn't that the GM mentally fills the role of looking around but that the GM tells you who/what you recognise - that is, someone else is relating your memories to you.
Right, this is something you've described in past discussions and it's what I had in mind. If my character walks into what is his hometown pub, I'll likely find it jarring if the GM says I don't know anyone there. It will feel like "Okay, clearly I know no one here because the GM doesn't want me to know anyone here" rather than "Oh no one I know happens to be here at the moment".
It all depends on how it's presented.
@Cadence went on to offer a few different takes, and I think some may lessen how jarring this kind of thing may be. But I also imagine that we all have personal preferences no these things, and the different methods will evoke different responses depending on the person.
We might have reasons for permitting knowledge checks but not Diplomacy-based flashbacks of the sort I suggest in my post, but those reasons can't be reasons to do with the temporal relationship between the fiction's "past" and its "present", given that both examples are identical in this particular respect.
Right, this is what I was getting at. I think that there is often an instinctual resistance to things like your Diplomacy example, and that resistance is often attributed to chronology, and I don't think that's all there is to it. There may one or more different/additional reasons for it, and those are what I'm curious about.
The nature of what is being "put into the past" apparently matters quite a bit to some people.
The authors of D&D (to my knowledge) haven't found the need to bring up time travel in discussing knowledge checks, the authors of BitD did when discussing flashbacks.
I agree it does seem to matter to some people.
Regarding flashbacks, I don't know what you mean about BitD bringing up time travel in relation to them. I don't think that happens at all, except perhaps to make it clear that's not what's happening. Is that what you mean? I think the Blades rules are typically much more clear and overt about process and what is happening at the table than many examples of D&D, particularly 5e, which is filled with vague descriptions of processes that can be interpreted many ways.
I think that D&D tends to approach the topic of knowledge checks and the like and how they establish past events in present play as being such a given that they don't even need to address it. Past events are established all the time in play.
I think that Flashbacks are a more active case compared to the passive case of D&D Knowledge checks, and so may warrant a comment to clarify what's actually happening, but they're otherwise very similar.