I guess that dependends on your definition of a power user. Some might see someone spending multiple hours a day with a given software sufficient to be called a "power user". If I had to make up a definition right now, I'd go for something like: Someone who invests a small(er) amount of time to e.g. configure the software to their needs or learns some keyboard shortcuts knowing it will save them a large(r) amount of time in the long run, by tiny savings spread over weeks (or decades). It's more about the mindset. With that definition it becomes clear why vi is often considered "power user only". With the frequency of product redesigns the commercial software sees, I can understand why many people hesitante to invest upfront.