@darkbard - Apocalypse World (which is still on my "coming up next" list) has clocks as an option for threats. It's not a technique I've used yet. I'm used to the method - most clearly articulated (in my view) by Luke Crane in BW GM advice - of GM authority over the way large-scale threats/events unfold, subject to a duty to honour player success and a permission to exploit/compound player failure or chosen inaction.
I have passing familiarity with
AW from discussions hereabouts over the years but have never picked up a copy. I
do own a copy of the
Burning Wheel Gold book, which I picked up a couple of years ago after conversations about that game piqued my interest, but I haven't found any time to read more than the first few chapters, and that maybe a year and a half ago....
I've pretty much always played with GM authority over large scale threats and have been exploring ways of tempering and/or mechanizing it to some degree. This is an attempt in that regard, though it still maintains some GM authority over what constitutes a viable reason for checking off a slice, how many slices get checked off at a time, and even how many slices at which to set the original clock.
Actually, the Clocks mechanics aren't a whole lot different from the Skill Challenge, excepting most Skill Challenges are implemented as a series of successive checks in response to cascading narrative focus, whereas the Clocks operate in the background much of the time, with other, immediate narrative concerns taking precedence.
And, again, this is pretty nebulous as I was still working out the details before play went on hiatus.