Pat Mussotte wrote on Jan 15^th, 2019 at 4:44pm:

In fact this plane was capable of 5000 feet runways for very special operations like maintenance

No doubt about that, but I'll bet the 707's in the video were very light (no cargo, no passengers, and not a lot of fuel). In that video, they probably did short hops to, and from, a nearby airport with a longer runway. ;)