For some reason I always (if reasonable, and that's often) climb and descend two steps at a time, like you describe. It's quick, and doesn't even tire much more than doing short-short-short, since while the exertion is a little higher, the entire staircase takes a lot less time.

At some point you get good enough at this stuff to descend a staircase, quickly, at a busy train station (somewhat; can't be too busy because then the stairs are too crowded) with no arm rests in range, while you hurry to the underground bicycle storage. There you take two steps down at a time, then get your bike up those stairs (bike in a gutter) in the same way, and not miss a stride when you jump on the bike to cycle to school.

It also feels really efficient. I've never fallen yet doing this stuff, though there have been cases while descending some staircase where I came a bit closer than I'd like.

Addendum: I don't count stairs, by the way. Apparently not nerdy enough.