"Doorknob to desk."
I’ve been using the term for years, but what does it mean, really? The simple answer is that it measures my travel time, my commute, from the time I leave my house to the time I reach my desk, ready to do work. It’s what’s implied that makes it less simple. By employing this obvious simplicity, I reduce all the variables concerning travel time of one’s method of travel to a single integer.
Going by car? You had to scrape the frost off the window, shovel the driveway, stop for gas, find a parking space, and walk from that spot to your place of employment. Going by bus? You had walking time to get to the stop, some minutes to wait for it to arrive, perhaps make a transfer with its own travel and wait. Going by bike? Fill tires and secure load before getting underway, then lockup and maybe a quick wipedown or change of clothes upon arrival.
What it also accomplishes is to eliminate bias. As a transit rider, car commuters routinely ask, “How long does it take you to get here by bus?” Implied in that question lies a bias that travel time is of utmost importance. I want to respond with a question of my own, “Why would that matter?” But I reply with a simple question: "Of course going by car might take less time, but it also costs me $14/day to park, and I have better things to do with a couple hundred a month. What do you value?"
In offering an integer for my travel time by bus or bike, I often get the reply, “Ha! I can get here in only 20 minutes!” In so doing, they measure a best case scenario, and then only the time from the moment a tire hits a road to the time they pull into the parking lot, as if all that other stuff on both ends doesn’t count. But it does. Worse, the majority of people I’ve conversed with, hundreds over 20+ years, employ a best-case scenario that involves no traffic lights, no traffic, and traveling 10 mph over the speed limit.
Doorknob to desk, at or below the speed limit, with car prep, fueling, scraping, shoveling, and parking issues included, levels the playing field, making those travel times comparable.
What D-to-D does not do is attempt to compare the subjective values of differing travel modes. A transit user can take a nap, but a driver and cyclist cannot. A transit rider can skip the snow shovel, read a book, send a text, and get work done on the way, something a motorist cannot do. A bicyclist is getting a workout and pays no travel cost, but is subjected to the elements. A motorist has great comfort, but at an order of magnitude greater cost. Being subjective, each person will value all these differently, and that’s fine.
This one measure, though, merely reduces travel time to a single value. Do with it what you will. I no longer value the shortest travel time as important. For me, cost is a big factor, so is personal health. Changing my mind on these has let me look at life differently from when I was one of those maniacs behind the wheel. It’s only a number, but you have to start somewhere.