It's true. Director Rian Johnson has released his extremely interesting proof-of-concept video for his hit time-travel movie Looper, and it was footage of Seven and Blade Runner that helped show Hollywood what he was trying to do — and convince them to let him make his movie.
When a director has a less-than-simple idea for a movie, and needs to explain it to Hollywood execs in order to get them to give him/her money, he/she usually makes one of these proof-of-concept videos. As Johnson revealed:
This is a strange curiosity I thought might be interesting - just after I finished the script for Looper but before we began preproduction I asked Joe to record some voice-over, and with help from my friend Ronen Verbit constructed this "fake trailer" using clips from other movies. This is a fairly common thing to do when you're trying to get a movie off the ground, but it was the first time I tried it. It was meant to show more some of the film's tone, and to show how the odd concept could be presented in a clear and compelling way in the marketing. Zach Johnson did the sketches. Note that we hadn't begun the casting process yet, and the clips were chosen just based on their visuals and not by who is in them.
It's very cool to me how closely this concept trailer, despite using footage from two very different movies, actually looks and feels like Looper. It's also probably worth noting that since Looper almost certainly helped Johnson land the gig for Star Wars: Episode VIII, we have Brad Pitt and Blade Runner to thank for that as well.