What I mean (in my subject line) is that when one plots out a trip, that crosses time zone lines, does the program include the gain/loss of time? Be it Google maps, or Delormes Street Atlas, or any other web or stand alone program.
I'll give an example (if my explanation is still clear as mud); I'm traveling from Columbus to Baton Rouge next month. Google says it will take 15 hrs for me (I-71-65-40-55-12). Should I be counting 14 hrs (because I gain a hour going from Eastern to Central), or does that 15 hrs already include the time gained?
Microsoft's discontinued Streets and Trips software (which I'm still using, for familiarity, it gives me a durable record of my travels, and works where no Internet connection or cellphone/wireless signal is available) will alert you to a time zone change, but let you figure out its effect. After all, it has no way of knowing whether, say, a planned trip from New Mexico to Arizona will be made in the summer (when New Mexico is on DST but most of Arizona isn't), or winter (when there is no time zone difference). I'm not sure how it handles the time zone difference for Navajo lands in Arizona (follow New Mexico time, along with that state's Navajo lands), or the Hopi enclave within Navajo lands (always follows Arizona time).
I'm not sure any trip planning software is smart enough to deal with border cities that unofficially follow the neighboring city's time zone, like Hyder AK (follows Pacific time like Stewart BC, rather than Alaska time like most of the rest of Alaska), Wendover UT and West Wendover NV (IIRC, both follow Nevada time even though Utah is in a different time zone), Flin Flon and Creighton SK (follow Flin Flon MB time, even when everywhere in Manitoba is on DST and almost everywhere else in Saskatchewan isn't), and Lloydminster SK (always follows Lloydminster AB time, which differs from normal Saskatchewan time in the winter).
It's a lot simpler to assume that the software is making no time zone adjustment, and figure out what if any adjustment you need to make.
My suggestion would be to use the same software to plot yourself a short itinerary across a time zone line and see what it does. Maybe use Columbus, Georgia (Eastern Time), to Phenix City, Alabama (Central Time, though most of the town uses Eastern due to Columbus being a bigger neighbor), and just plot it out from one end of the 13th Street Bridge to the other. It's less than a mile, so the time should reflect that.
I just attempted to do that using Apple Maps on my iPad but it kept trying to "correct" the starting location to somewhere else, so I gave up.
Edited to add: I just tried it in Google Maps. It cited a distance of 0.3 miles across the river and said it would take one minute. So it's giving actual travel time.
I would imagine that they do by 2017 standards.
I know from experience that Apple Maps shows the travel time in terms of actual hours and minutes of travel, but the app also displays a running ETA clock that does take time zone changes into account.
For example, if I was five minutes east of the ET/CT boundary and entered a destination that was five minutes west of the boundary, I'd see:
Current time: 8:10 a.m.
Travel time: 10 min.
Distance: 10 mi.
7:20 a.m. arrival