This just shows that the percentage of total time a function takes is really not the thing you should be looking at when optimizing code and you want to know how much faster your code really is.
For example, say your function f() takes 100% of the time. You then make it twice as fast. You look at the percentage, and, surprise, it still is taking 100% of the time!
For example, say your function f() takes 100% of the time. You then make it twice as fast. You look at the percentage, and, surprise, it still is taking 100% of the time!