I believe part of is experience and distractions. My boys' outdoor time is limited to our daily leashed walks. They are in tune with me, but when a distraction presents itself -- like the UPS delivery truck -- the boys lose their minds!
The boys have gotten loose a few times. They seem to only respond to fear in my voice. Like Piper, they aren't treat motivated outdoors.
Using the 25 ft leash with Piper is good. Keep practicing outdoor commands. I've noticed with my guys that they easily forget things when we haven't done them in a long time, like how to behave walking in heavy people traffic on a sidewalk.