This might seem a bit naive, but does an open entry in the tech log ground the aircraft until the fault has been cleared by an engineer, or are captains allowed to fly the aircraft with acceptable deferred faults. i.e something that they are aware of but are happy that the aircraft is safe to fly.
i think the second option is how the military work, with acceptable faults signed for by the pilot to show understanding and that he / she is happy with the snag.