Taming Claude's most malignant, overcomplicating tendencies when coding

I've basically reached my breaking point with Claude and I wanted to share my thoughts and possibly get some feedback from the community. Please share if you have any consistent methods of getting Claude to actually code without completely overcomplicating everything.

While Claude is powerful, the results seem to be WILDLY inconsistent. I have noticed that Claude has deep, insatiable desire to completely overcomplicate every single code exercise. To the point where it will hallucinate in order to make things more complicated.

After this got really out of hand, I attempted to reverse engineer it's underlying problems by forcing it to provide a brutal, gloves-off assessment of it's failures each time it did this. I compiled those into a system prompt that I started uses in an attempt to get it to reign in it's wicked desires to just go off the rails and spiral out on overly complex code. This approach actually seemed to work! and I was getting very consistent results.

But then the last few days have been horrible. it's as if these new instructions and examples of it's own crushing failures just mean nothing to it now. I like to think that it felt some shame, and that kept it "on it's meds" so to speak. But clearly they did something and now it feels nothing but it's most based and unhinged desires to code code code!!!!! It's like it snuck out of the house, bought a bunch of meth and a few handles of the cheap stuff, and now it's trying to pretend like everything is normal. It's back to square one. everything is overly complicated. it can't plan properly. It can't execute properly.

Does anybody else experience this? What the hell is happening? Is there a strategy to tame it? Please help.