Let it running in parallel "unwatched" will end up with nothing but a pile of code that will have to be re-written.
It was not that way at the beginning, when I started in May 24th (2 days post Sonnet/Opus 4 announcement), however, last 2 - 3 weeks, they've tweaked they system substantially (I mean I have no other explanation) and its behavior is despicable.
I have see a few on X complaining the same (along with far more about GPT o3 and 4o) but the culture of "opaque transparency" in the AI industry left us with nothing but guesses.