[From Bruce Abbott (970413.1900 EST)]
As the rate of nutrient increase goes from negative through zero to highly
positive, the intertumble time decreases proportionately.
Sorry, what I meant to convey is that the intertumble time _in_creases
proportionately. (Although I wrote "intertumble time," I think my brain was
still thinking in terms of tumble _rate_, the variable Rick had in mind as
being "essentially tumble probability.")
Bruce