This answer is coming from a new dad with a now 6 week old, and a software engineer who understand why you're coming at it from the angle that you are.
- I want to know what your experience with newborns is and if you were able to "train" them to be more peaceful.
- Reward leads to much better results. The only problem would be of how to make a very young child "make want" something to be able to reward it.
- I need to get him under control (and us a peaceful night)
Your expectations are ahead of the curve here.
Right now, your child is not a rational being. He isn't choosing to behave the way he does. His reactions are all instinctive and there's a very simple cause (e.g. hunger) and effect (mouth opening, and eventually crying) to his actions.
You can only train those who are able to reason about their desires and behaviors, and your child is simply not capable of that level of reasoning yet.
Right now, you are in the territory of "on demand" parenting. Your child will alert you (without clear instructions) that something is amiss, and it is up to you to spring into action, figure out what the issue is, and fix it. That is all you can do right now. You cannot get him to willfully change his behavior, or not respond to something he experiences.
Sometimes he freaks out even when held and it is hard to tell what he needs even if he is clean and fed.
Clean and fed are not the only two problems that you have to address. From experience, there are 4 very distinct and common issues:
- Dirty diaper
- Cramps/sickness/general discomfort
This is by no means an exhaustive list, and not everything is easy to troubleshoot or figure out. Just the other day, my child started crying loudly as if he was dealing with severe cramps. It ended up being nothing more than his feet sticking out of the blanket and having cold feet.
Not every child will be upset the same way by the same experiences. This is something you have to figure out for your child. Eventually, you'll figure out the likely suspects based on when/how they cry.
Needs cuddles (Mostly from my wife, this is a problem since he ALWAYS wants to be held, even at night when it is sleeping time. I can't judge him for that though since my wife and I are both cuddle addicts.)
While your child currently is not a rational being, that doesn't mean that he can't get used to something and end up struggling without it.
There are certain benefits to sleeping on mom and dad. There's slight movement and rocking, there's warmth, both breathing and heartbeats provide a soothing sound, and having an arm resting on them can provide some snuggly pressure.
As much as these are all nice things that can help an upset baby settle down, overreliance on these tools may lead your baby to be unable to soothe in absence of those tools. In essence, you are creating a baby that needs to sleep on its parents.
We've made a similar mistake with playing white noise during naps. It very much helps in having him sleep through minor disturbances in the household, but we overused it and he's now very easy to wake up when he hears any sound.
Comparatively, my friends' newborn was able to sleep through their German shepherd loudly barking, because it was such a common occurrence that they simply learned to sleep through.
If you want to avoid the inherent dependency to need to sleep on Mom or Dad, you're going to have to ween them off it and get used to sleeping in a bed by themselves.