Baaaaah, that's a load of shit. Weapons tech is way beyond the need for physically sighting in almost any cannon-related system. Self-checking and correcting digital sight systems are definitely possible to make at this point in time. But as always, the problem is creating and then implementing said technology... Always a long and arduous process.
... Not that weapon R&D time 'n money is best spent on targeting systems and such, of course.