Maybe your ideal cadence range is similar to your ideal running pace range. Runners don't change their pace much going up hills or down hills or on the flats, and most endurance runners seem to maintain a pace of around 85 to 95 strides per minute, I think I read somewhere. Rather than running at the equivalent of a mashing pace for climbing hills, runners subtly adjust their stride length---the equivalent of shifting closely spaced gears to maintain a steady cadence.
That said, I'll now head out on my track bike with a 71" gear to fool around in the hills of northern Baltimore County. I should know better.