More than a few times lately--well, shoot, over the years--I've read comments and blogposts about tuite and kyusho from people that are--well, they're just interesting, I'll put it that way. People will tell you to rap someone in the temple with a backfist--a technique involving a striking surface about the size of a fifty-cent piece impacting a target about the size of a fifty-cent piece--whilst simultaneously deriding nerve strikes (I am not making this up. I read a piece by one of the highest-ranking Isshin Ryu masters in North America doing this very thing.) They'll tell you that tuite is too complex, too much of a "fancy technique," to work in combat, under stressful conditions.
God knows I don't claim to be an expert on either kyusho or tuite, but I am pretty sure that anyone telling you such things isn't all that good at either one. Tuite is not very complex, not really, at least what I have been shown. It is simply the practical application of anatomy and body mechanics in a defensive situation. You are drilling the motions, over and over and over, in kata. You do not, under stress, have to rummage through your memory to find appropriate techniques any more than you have to rummage through your memory for appropriate driving maneuvers when you are trying to avoid an accident. Just like striking techniques, tuite kind of "pops out" of you when appropriate, if you are doing the practice. And if you are seeking techniques that do not require that you practice them in order for them to be readily effective for you, I would suggest that you are kind of wasting your time practicing martial arts in the first place.
Tuite is darned effective, once it becomes natural to you. I keep going back to the example of my own instructor, but that's because he's the perfect illustration. Doggone it, the man's a fairly smallish, ill, weak, oxygen patient of sixty-two years age, and he can quickly and easily overpower either me or my son with tuite. It doesn't require muscle. It can slam you to the deck in a heartbeat.
All I'll say about nerve strikes here is that in my limited experience, as you become more familiar with them, the vulnerable areas become easier to find and hit. I have learned painfully from my son that eventually, it becomes darn hard to miss those nerves. Dadgummit, the booger hardly ever misses my nerves...
All of which is to suggest that if you are interested in the subject, you visit this post by Openhand. It's a short education in the subject.