The essay defined hacker in a clear and focused manner. Clearly it's broader than the definition than you would choose, but I suspect it might also exclude things you might define as hacking.

My impression is that people expect hacking to require the use of technology, but that doesn't necessarily mean what we would expect it to. A chopstick is after all a technological tool.

We might restrict it to electricity, but then that might preclude mechanical devices, so perhaps we allow machinery in general, but then a pair of chopsticks might be a sort of simple machine...

Lets all forget that the word hacker had nothing to with programming and was popularized by a bunch of dudes fiddling with toy trains.

Do you think RMS hacked his lunch by adding a little extra salt?

Only if adding salt was somehow forbidden, would push the boundaries of known human experience, or playfully exciting in some way. I do think the Chefs on Planet Green's Future Food are hackers in their own way: http://planetgreen.discovery.com/tv/future-food/meet-chefs.h... - a while ago I saw them cook food with liquid nitrogen and preparing numerous dishes using nothing but road-side weeds spiked with miracle fruit.

But if RMS calls Lady Gaga a hacker then she must be one. It's RMS!