Klingons can always use coercion...Kidnap some fed techies and bob's your uncle - new warp drives, shields, weapons, <other treknology goes here>. No thought required and Klinks can go on being mindless savages.
lol- Our own RL history proves that doesn't work as well as expected. Under duress many people blank out or just find the moral turpitude to not give the correct information and such tactics end up going nowhere.
While any person will eventually talk under torture, not all that talking is helpful or what one is looking for to further one's goals.