even without the soft spots, if you're trying to torp it.. it's not like you'd exactly miss the behemoth... hell you could probably use the torps as dumbfires on that thing.
You can probably use torpedoes as dumb fires on anything, they just wouldn't be particularly effective - the special thing about torpedoes is that they skip through a target's shields.
That is correct. The idea that torpedoes skip shields was an essential part of WC2. The WC3/4 engine treats them like big explosives, but still requires the lock so as to imply that they're finding a shield frequency.