The most useful admission here is that intuition is what fails: the team stepped back because performance work was not going as fast as they wanted and found their instincts were leading them astray. The mechanism is that bottlenecks hide others — you remove the visible one and uncover a worse problem that was masked behind it, which is why a correct fix so often moves no numbers. Their answer is to survey broadly before drilling in, explicitly checking whether the processor back end is worse, finding it is not, and setting it aside. The diagnostic figure is instructions per cycle averaging below one against hardware capable of eight to twelve, which reframes the problem from slow code to an idle processor. Every fix that follows is about memory layout rather than logic, and returns nearly twenty per cent more throughput from configuration alone.
