The sense that I’ve gotten (from my own experience, from anecdotes about startup founders, and from some of Anna’s examples) is that there’s not much distinction between “falling” and “trough,” or between “rising” and “peak.” We’re looking at a phenomenon of RAPID, LARGE swings, such that you’re basically at one place one day, and in a completely different one the next (not that the shifts happen daily—just that they’re abrupt).
In other words, the way we chose to describe it might make it seem like there’s a larger distinction, there, but I think what you’re labeling “peaks” and “troughs” are actually the same places we were trying to talk about.
[Coauthor’s note] If anyone is willing to offer me karma by upvoting this comment, such that I can post my own stuff someday instead of piggybacking on Anna, I’d appreciate it.