Only in that it doesn't apply. Certainly, if doors clenched like two fists, they might stop a punch better than two palms. But the interlocking as illustrated by Michael isn't any more protective against a fist than flat palms. I translated the "punch" in scale as a battering-ram, which you agreed wouldn't be used in a spaceship. A phaser, which might be used in a spaceship, wouldn't care if it burned through straight edges or toothy edges or solid walls. No, but you implied a similarity of all spaceship-y-ness. What I'm objecting to are 1. non-functionality 2. inconsistency with the stated purpose of the vessel 3. unnecessary complication which would add to the operating cost and detract from the safety of any vessel. I didn't. Crew comfort was very low on my priorities. You brought up life-and-death situations in which a fast-closing mechanical door makes sense. I do not see the practicality of putting vault-like doors on living quarters. They add a huge amount of weight to the ship without adding to structural strength. From a purely engineering pov, a skinny perspex sheet that slides over a wall, rather than into it makes more sense than making two fat pockets inside the wall on either side of an opening. If you wanted extra strength, have two layers, inside and outside the cabin, so that the door forms an envelope over the wall, instead of the other way around. Less piercing of bulkheads the better, no? I brought up one situation in which a manually operated door would make sense. I briefly mentioned another: energy saving. Like when you're running so low on power that you turn off life-support to all but one deck - in which case, either all doors are sealed shut or stuck open. How's that logical? The logic of a war-ship is different from the logic of a freighter is different from the logic of an orbiting repair station. I mentioned particulars. Was always into specifics. Stating my opinion as the interested audience. When did I mention comfort? I did say people are supposed to be living on exploration ships and space stations. The next generation Enterprise certainly does look spacious (wastefully so) and comfortable, with no stupid doors. I'm okay with that. I did say that, functionally, bedrooms and offices don't need to be outfitted like tanks or bank-vaults, and that doors on anything should have a manual option - if only in case of a slow leak of something.