I am in late pre-rocketry game and have reached most of the map. While I have transport tubes, I still have long commutes.
The issue I am encountering is that dupes will regularly travel across half the map, do one thing, and then travel back to the other side of the map to do something else—wasting huge amounts of time. You could have a number of things to do in the area but the dupe will often do only one thing—leading to a big slow down in building. Sometimes this will be because the dupe only carries a certain number of resources (suck as 2500g of metal) but even if a number of dig tasks are assigned the dupe will still run back after mining of of the tiles they could potentially do.
Perhaps dupes should have their tasks re-evaluted after a long commute?
Difficult to reproduce. Try setting up an extensive transport tube network and have a number of tasks all over the map. Have one group of tasks (such as dig; not mopping as that seems more robust) all in one area. Some dupes will mine once and then go to do something else. I see a lot of this due to having most of map settled and have tubes all over the map and have many auto-harvest tasks queued.