Usability vs User Experience

Theorists! Speak out!

1. How do you think it is right to live with these words?
2. Do not give examples where these two concepts are closely intersected? (collaborate, conflict)

ps
Found on this issue a very simple and intelligible article (in English).
Here, Usability is compared to a modern autobahn: many lanes, a direct track, the absence of intersections and traffic lights, absolutely transparent navigation on information boards, and at the same time a boring, dream-like movement.
User experience is a mountain serpentine road: with sharp, uncomfortable driving turns, with a real danger of falling off a cliff, but at the same time passing through very picturesque places, with fresh mountain air overboard, a road that leaves you feeling an interesting adventure.

Google example

The connection of all Google subprojects (gmail, calendar, alert, history) with each other can not be called usable. Many gmail users still do not know about the existence of other pleasant services.
But, at the same time, the very moment of discovering these services, which, as it were, is not hidden, but does not catch the eye, for each user it turns out to be a personal experienced experience, a kind of revelation (=
It makes you get attached to these services much more than if the user saw all the projects in a good affordable design and would receive them as a banal advertisement.