How did they do it?

How did they make opus 5.5? genuinely, how?? when i saw the benchmarks and pricing, I was impressed. but then i started working with it, and seeing what other people have made, and my mind's been genuinely blown... how did they do it? how did they make a model so smart, that isn't benchmaxxed to hell and back, and is somehow actually cheaper than not just fable, but even the previous levels of opus? and all openai could do is make their own models cheaper without improving their intelligence at all. how does anthropic do it? are they magicians? or are we seeing the first fruits of RSI? if this is possible now, i can barely even begin to imagine what's possible in a year, maybe even in the next 3 months.