Not quite. Run your tests on an old machine. I remember testing some software over a slow dial-up line (1990s) and it was possible to see how slowly certain a

Not quite. Run your tests on an old machine. I remember testing some software over a slow dial-up line (1990s) and it was possible to see how slowly certain actions were painted on the screen. Being able to see that allowed me to make optimisations I wouldn't otherwise have considered.