Yes, yes it is. Simply asserting the opposite doesn't suddenly invalidate an entire industry's decades worth of experience. One good point from the essay thoug

Yes, yes it is. Simply asserting the opposite doesn't suddenly invalidate an entire industry's decades worth of experience. One good point from the essay though is Knuth's example of 12% speed increase for low effort is definitely worth doing. I agree. A better way of putting things is: Considering low effort, small performance improvements that don't affect other factors such as code readability or system maintainability is not "premature optimization". If you are considering performance "in the small" and it affects maintainability you are indeed prematurely optmizing.