Actually even on a modern CPU that property lookup does add another ~10% penalty. Granted it's like a .1 second difference out of a second runtime for 10m itera

Actually even on a modern CPU that property lookup does add another ~10% penalty. Granted it's like a .1 second difference out of a second runtime for 10m iterations, but it's measurable! Although I wouldn't be using python on those data sizes usually :)