How do you use a geartronic transmission?

[BlackBart]

I never use it. I can't see what it's good for? Sounds like just a sale gimmick to me.
EDIT: I mean out of all people that has this auto/manual feature, how often do they really use it?

For going down steep passes and not cooking your brakes by riding them for miles. You keep it in 4th, or 3rd, to hold it back from coasting.

Around town it's kind of silly.