For me, intuitiveness is defined by how quickly a new user (i.e. a newbie) can start using something. You say,
> Unfortunately, we seem to conflate “intuitiveness” with “intuitiveness for newbies”.
I either can't think of another kind of "intuitiveness" or we have different ideas of what constitutes a "newbie".
> However, if you’re creating new power features, those features will always be better served if they are more intuitive for the intended users, I.e. power users. (conversely, they will be worse off for power users if they are designed to be intuitive to newbies).
Ok, yeah we have different ideas of what's a "newbie", and apparently what's a "power user". I think your definitions depend on how much experience they have with computers in general. Actually, no. I think it depends on what kind of programs a user has experience with. Like users of GUI are newbies and users of CLI are power-users. That's the only way making something intuitive for power users makes sense. After all, making something intuitive is about following existing conventions, so we're differentiating "newbies" vs "power-users" based on the conventions they follow. Sorry, if I misunderstood you here.
For me, "newbie" and "power user" do not imply anything about their experience with other related systems, only with the system that is the object of conversation. In that respect, by definition, you can't make something intuitive for power users. Every person on first touching a system (a software program or otherwise) is a newbie, regardless if that newbie is not a newbie anymore in another system.
A "power user", for me, is someone willing to accept a learning curve to best do whatever a system is designed to do. That basically means someone that is willing to read a manual of what he uses, though they can also do other things like practicing and reading the source.
So, on first touching a piece of software, everyone is a newbie, and some become power-users.
Designing for intuitiveness vs power is about favoring those that wouldn't be willing to study a little and become power-users vs those that would.
When I say that, I don't mean that power will always come at the cost of intuitiveness, but I do mean that some design decisions could be made that favor power at the cost of intuitiveness.
An example of this is vi's modal editing and its normal mode language. If you put someone that's never touched a computer before in front of 2 computers, one with Windows's notepad and the other with vi, with no documentation whatsoever of either, which will he be able to use most effectively first? notepad. The user just needs to press any letter key and he'll see the characters appear on screen. He'll be writing paragraphs in seconds (if his lack of touchtyping ability wasn't an issue). In this respect, vi's modal editing is not intuitive. It's a cost vi paid for implementing a mode that allowed a whole keyboard's worth of buttons to communicate to vi different editing and navigation procedures most efficiently.
> I believe that intuitiveness always helps with power.
With the context of the above, getting rid of normal mode would make vi more intuitive, but it would certainly not help with power.