I've seen this kind of thread before, but not exactly in-depth. I've been thinking about this for a while now, what kind of author statements/information would be considered valid and what kind of statements/information would be consider invalid? I figure it's rather difficult to word it, so I decided to be more specific and lay some examples: 1. The author has written 2-3 works. Character A from series X has been fan-calced to be fighting/reacting at relativistic speeds. Statements comes from the author that character B from series Z can fight or even overwhelm character A without much difficulty. Character B from series Z hasn't got any specific calculations regarding his speed, but hasn't got anything exactly contradicting it either. It's not a multiverse, it's two separate works taking place in two completely different worlds. ........a) said statement was an answer in an interview ........b) said statement was a twitter answer to a fan-question ........c) said statement can be found on the author's website/blog/databook HE's written (without assistants/interference) 2. Imagine the same, but DC/Durability. This is where things are more interesting. If character A from series X has been proven to have continent level DC/Durability and character B from series Z is somewhere around multi-city block. Case-by-case basis pops to your mind, doesn't it? We have then Nasu tomorrow going on about how Fate/ Servants can physically overwhelm Types or Ado Edem or whoever has higher durability than Servants' DC. Okay, another DC related question, I don't know, let's not go with HST, YYH's author comes with a databook where it says that the rock in demon world is 100 times more durable than in our world or Blame's author comes tomorrow with a databook stating that the megastructure can easily withstand planet-level energies. Great, isn't it? How would you look at it though? 3. About Sci Fi vs Fantasy/series relying on "magic". Situation: we're given a weapon from a Sci Fi series. I'll pick a more known one, Angel's Arm. We're told in the databook or the author's blog or twitter that the Angel's arm can destroy a planet or even more and it moves at FTL speeds. Or we can have Blame's author saying that the GBE gun can actually destroy a star if properly used/charged and that it moves at FTL speeds in reality. Sci Fi is nice, right? Next thing we're given Saber's Excalibur from Fate/series and we're told that an Excalibur can destroy a planet too. Pretty damn inconsistent, isn't it? But sure, let me pick a relatively less liked series: tomorrow Oda states on his blog/website/twitter that Whitebeard can actually specifically destroy the planet/split it into half/whatever. Or that Luffy can pulverize a huge island, but he doesn't do that due to CIS issues. 4. Downgrading characters. Fan calcs said character A from series X has moved at relativistic speeds in 2 instances, but otherwise hasn't got showings (calculated) lower than that. Character B form series Z has been shown constantly to move at low hypersonic speeds (and even lower) in hundreds of instances. Author (of the both series, that take place in separate worlds) comes and tells you that nope, character B is definitely faster than character A. same: twitter/interview/databook/blogs/author website. I can't think of any other more specific stuff, but this should suffice for now.