Ever 17 - The Out of Infinity -

That's totally the gut punch ending of the lot. Just like in Saving Private Ryan or The Dirty Dozen, though it's on another level because at that point YOU are supposed to be the character. It's hugely effective in some ways, but in others, that kind of thing always feels like a cheap shot. I'm still ambivalent about this ending, and the technique they use in general.

Anyone get why Takeshi has that two frame epilogue that says "1. Mai 2034 Eine Geschichte setzt auf"(translation I think is "May 1, 2034 A story/history begins"). This escaped me.

I think you're reading too much into this here. I'd say this is just a piece that would have always belonged there, but could not be shown before you've played to the 'true ending' since it would have been too spoilery. (By the way, the correct quote and translation should be "Eine Geschichte setzt auf 1 Mai, 2034 fort." -> "A story continues on May 1, 2034.", although the German's not quite correct - it should be "am", not "auf".) It only signifies the fact that the complete story that begins with Takeshi in 2017 continues with Hokuto in 2034.

That makes sense, but then why bother to include it? It is at that point redundant. And if the game claims Coco's ending is the "true" ending, then some of the events of the other scenarios clearly didn't happen or become impossible, such as Sora's ending. I see I also botched my german word order and confused aufsetzen and fortsetzen. Been too long I guess.

Well, it's not that they 'didn't happen'. I guess you can call them different parallel worlds BW has seen. They do exist as well, but the 'true ending' is what you could consider the best of them, where everyone gets a happy ending, or at least something close to one.

Why include it? Well, yes, it might be a bit redundant, but it's not the only epilogue there, is it? Since You and Sara have theirs as well (and I don't remember it quite well at the moment, but I think I did not see You's the first time either), it makes sense to add one to the 2017 routes as well. It's just a small detail connecting the 2017 and 2034 stories. /rambling

First was the ending scene with Sora when Takeshi tells her the story of Pygmalian. The story seems out of place when I played the Tsugumi line initially, but it played out wonderfully in the end.
Second was the Tsugumi/Sara/Kid reunion.

I'm quite confident that the mass of water entering the water/airlock is substantially greater than the mass of one person leaving a submarine. I guess we can pretend there was a manual bilge pump that the writers neglected to mention.

Takeshi and Tsugumi are in a submarine with 2 rooms, one is the bigger main component and the other the smaller airtight space which leads to the outside. Takeshi went to the other space and locked the door connecting the 2 spaces shut. He thens open the lock to the outside and got out, this made water go in, when the water filled up that space, the submarine is the same as a submarine with a single space. Since the door connecting outside is not shut, the water density should be the same. Thats why it should float?
My physics isnt that good so if anything wrong, correct me..

You're just not balancing the equation before and afterwards. You're right, there are two chambers, the operational chamber and the decompression chamber.

1)The decompression chamber starts out filled with 1 cubic meter of air, which is slightly more than 1kg.
2)A person enters the decompression chamber from the operational chamber, closes the middle door and opens the outer door... 1kg worth of air and 60kg worth of human leave the submarine while 1000kg worth of water enter. You've now got the same volume object, but it's mass is over 900kg greater than before he jumped ship.
3) The submarine is unpowered, so the normal means of jettisoning the water taken in are likely non-operational. Hence, that's why I say there needs to be a manual bilge pump that tsugumi can operate yet isn't mentioned in the script.

I don't know if such things are standard in a sumbarine. On one hand, it seems like a sensible safety precaution... and on the other hand it's a non-trivial mass which I have no idea how effective it would be in an emergency situation.

vertical axis:
(pointing upwards) buoyant force = density of liquid x volume displaced(vol of compartment tsugumi is in) x acceleration due to gravity

(pointing downwards) mass of whole sub that cant escape the sub(mass of tsugumi + mass of sub) x acceleration due to gravity

the the 1000kg of water should only apply if takeshi went out and then closed the door after 1000kg of water flooded into the small compartment.

sub will float if net force is upwards.

You're once again missing the small fact that the outer door will remain open. You can't consider the water an additional weight in this case. If anything, the only thing you can change here is deducting that cubic meter of decompression chamber from the total volume of the submarine.

Once the decompression chamber has been flooded, it is completely irrelevant whether or not the exterior door is closed. The whole concept of bouyancy is you are displacing a dense fluid with a volume that has a lesser AVERAGE mass than the fluid it is submerged in.

Yes you can consider that the exposed compression chamber is simply a reduction of the volume of the submarine. However, remember that density is mass/volume. Decreasing the volume while maintaining a constant mass means the average density is increase, and thus more likely to sink. In this case, the loss of one person's mass has a much smaller impact on the bouyancy of the submarine than the loss of the compression chamber's volume.

I'll illustrate this with a scenerio easily visualized. Imagine a 1ft cube of styrofoam encased in a form fitting watertight container. Embedded into this styrofoam is a steel ball 1 inch in diameter. The casing is made out of a very dense material, such that the whole assembly is perfectly neutrally buoyant.

Now remove the steel ball and slice the foam in half. Fill in that space with water. If it makes you feel better, poke a hole in the casing to simulate an open door. Do you think that the object will still float? It won't, because the volume of the light material is significantly reduced such that it can no longer displace enough water to lift the heavy casing.

This illustration is a worse case than the actual submarine, but it's only to express the concept. The actual numbers I listed earier should show that the submarine assembly is less buoyant after Takeshi leaves than before. As I keep saying- unmentioned manual bilge pump fills the plot hole.