@inthehands the os optimizes background tasks to run on performance cores, and in many cases, will prevent those low level tasks from running on a performance core.
If you have a threaded web browser and you are switching back and forth between that and your IDE, and the OS kicks off a check for updates, then spotlight indexing in the background, and who knows what else, the OS tasks will not be preempting your work
I only notice slowdowns when I run out of ram. Not the case on Intel.