Ahhh - so much to say here. This is long, long, long. But I would have drunk it up when I was in your shoes. So I hope it's helpful to you.

First of all my DS7 (PG and 2e-dyslexic) has had a similar "life cycle" to other kids described here. IF ONLY I had known about this board when he was 3 years old. It could have given me a glimmer of hope and a bunch more self-confidence.

Re parental responses: You really have to toss out much of what you will be told will help your child. Sure - try it. But when it doesn't work, don't lay awake at night questioning your parenting. As you've seen here, lots of strategies that work for neurotypical (NT) kids, are at best useless, at worst counterproductive for GT kids. Here are few examples that I can smile about now. These are all quotes that my DH had the prescience to write down:

(a) At 2.5: "Mom, I don't want to do it. Why would a sticker change my mind?"
(b) At 3.5, when put into a timeout: "You can make me sit here, but it WON'T MAKE ME SAD." Yes, timeouts were counterproductive.
(c) At 5.5, when he declined to go to a pirate party: "Mom, there's just going to pretend swords, and chaos, and somebody's going to end up getting hurt." This was one of the first times he self-regulated re activities, based on knowing they would be overwhelming to him.

Re behavior and impulse control: DS has had many of the same struggles you and others describe. The biggest battle in supporting him has been to get the individual teachers, principals, etc. to understand that this really isn't volitional behavior on his part. Over time, I have developed some responses to classic comments:

(a) "He made a bad choice." No - he didn't. If he could have chosen he would never have done this. His impulse overwhelmed his capacity for control and he acted badly. Let's work on the behavior together, because it is unacceptable. But you won't get anywhere with him until you are on board with the fact that his behavior is not a choice.

(b) "He did [x bad thing] and it was totally unprovoked." No - it wasn't. You don't see the provocation, but it's there. Maybe it's something the kid did days ago. Maybe it's something that wouldn't provoke NT kids but that drives my PG/2e kid wild with upset. Or maybe it's something my uber-intuitive-pattern-spotting DS knew the kid was ABOUT to do, based on the same pattern playing out over and over. The [bad thing] is unacceptable. Let's work on it together. But you will never get anywhere with him until you are on board with the fact that his actions are never "unprovoked." They are always rational (at least to him) and responsive - even if you don't see it.

(c) "He just needs to stop and think." Well, yes. But do you think if he COULD stop and think, he wouldn't? This kid is all about thinking. It's the stop part that is eluding him. Please help me help him to FIND that moment for reflection. When he has it, these problems will evaporate.

The upshot of all this: traditional rewards, punishments, discipline whatever you want to call it don't work for many gifted kids for the fundamental reason that they are based on anassumption that the kid has a CHOICE and is DECIDING to act badly. When that faulty assumption dictates strategies, the kid is left feeling horrible, defective, stupid and many other bad things. I could go on and on. This really is the fundamental point. I think we should make the kid work HARD toward finding the moment to stop and think. But don't pretend they have that moment when they don't.

Just a look down the road ahead for you: Things are not perfect for us, but they are really, truly improving. When DS is rested and fed and not overwhelmed, he is IS able to find that moment to stop and think. And sometimes, when his most trusted adults are close by, he can even find that moment if he is tired or overwhelmed.

I try to collect these times in my mind, so I can show them to him when he despairs. Because, that's the hardest thing right now - his despair. He's in the soup so to speak, so he cannot see that he is doing better and better. Instead, he says things like "I was just born to be bad and I'll never get better." And of course for a perfectionist kid (like yours probably is), "better" has to mean "perfect." It's dark times for me as a Mom, when he says stuff like this. But thank goodness I can trot out specific examples of how he is taking control of himself, bit by bit. I appeal to him "as a scientist," and he has to admit what the data show!

If you need it - there's hard science to help explain some of this. Gifted kids tend to develop impulse control later, and the more gifted, the more delayed (as a generalized statement). And honestly - having cold, hard, kid-specific data (IQ, achievement, etc.) to tell me just how much of a brain difference he is handling, has helped me stay on an even keel on the tougher days.

I wish you the best as you go through the time that was toughest for us (from 3.5-5.5). Just know that your little one is trying so hard to deal with things other kids don't have to handle. And YOU are dealing with things other parents don't have to handle. And even by asking these questions, you are doing a great job as a loving parent.