Timo, In your example, the locking mechanism is the weakest part of the design if it is vulnerable from behind; thieves wouldn't use that method were it not.
Let's not confuse "weak" with "vulnerable". Those two are typically the exact opposites in military applications, because one attempts to cover vulnerabilities with strength.
Even "vulnerable" is a relative issue. If loss of one component can jeopardize the entire system, then that part might be considered vulnerable even when it is the best protected - say, the king on the battlefield, behind his armies, or the lock in the armored door, behind the strongest armor. Whether loss of docking latches could jeopardize a
Galaxy is not in question as such; but whether such loss would present a greater jeopardy, or present it with lesser effort, than an attack directed at some other component, is far from said.
In an armored car, the lock latches and the hinges are at least as strong as the door itself, and typically stronger. And while the lock mechanism may be vulnerable even though the latches are strong, the hinges are typically neither weak nor vulnerable, despite being moving parts. So one needs expert knowledge on which parts of the system to attack for the desired outcome (in this case, quickest possible entry) - and sometimes the best option is to go directly against the armor and punch a man-sized hole in it, rather than try and find single points of failure that may not really be there.
And were the saucer latches the strongest part of the ship, then most designs -- regardless of a separation feature -- would incorporate that construction method.
You mean, dedicate the whole deck to structural integrity? You couldn't build starships that way. Most of the ship would have to be made of weaker stuff so that it would have at least some functionality apart from just "holding together".
as I said, the force at work is twisting or shearing of the clamps.
But the same force is twisting and shearing at the neck, which doesn't mind the treatment. We're thus talking about a highly hypothetical situation where the enemy would be able to overcome the considerable safety marigins of the structures, yet would still decide to concentrate on the docking latches (either by firing at them, or firing in a manner that endangers them) instead of striking at structures of direct tactical worth. And as pointed out, mechanical vulnerability only seems to become a factor at total and prolonged power loss - a situation where such vulnerability really doesn't matter much anyway, as the enemy can wreak his desired sort of havoc with impunity and probably doesn't bother with indirect attacks such as attempts to mechanically fatigue the spaceframe.
It's nice to have the nacelles away from the ship for a bit of a safety margin; but if I have enemies who want to shear off the nacelles or the families, I'd rather travel compact.
I wonder if the lack of nacelle clearance is a factor in the inferior warp performance of the
Defiant. If not, it indeed makes no sense for Starfleet to keep on building ships with long, slender engine pylons. Although conversely, since Starfleet does build that way, we must infer that this is the exact right thing to do, and doesn't pose any risks of importance.
Timo Saloniemi