I found this very interesting. My job is a performance test analyst, and we often find that performance issues in software is not the software itself, but the users perceptions of it. Have a user wait for something to happen with nothing going on, instant 'its running slow' report. Add a spinner, progress bar, literally any user cue that something is still happening and they'll be more tolerant. The software could actually be slower because it has to deal with updating the screen as well as the job it's trying to do, but users will be happy about it.