Great article, Lorel -- although my son seems to have honed in on what he wants to do (I have made sure he is aware that the door is open to change if he desires it, though), he has a number of friends that seem to be caught in that trap.
You said, "... sometimes even mature adults as well."
That kind of hit home, even though I'm not gifted. I'm a stage in my life where I'm trying to decide what to do next, now that DS will be going to college f/t in the fall. (Until then, I seem to be mostly booked with driving him to and from activities, so a slight reprieve!) I don't really want to go back to what I used to do -- programming -- and even if I did, I would need to relearn it all, plus new stuff, since it has been so long. But I think about the options, and am having my own troubles narrowing down my focus, trying to figure out how to proceed.
Somehow, "You can have it all" is often interpreted as "You MUST have it all" -- and that is definitely overwhelming!
I think, too, it isn't just that they can excel in multiple areas, but that they can have multiple, diverse, passions. Passion can sometimes carry the day when raw talent isn't there as much as they might like.